Top Banner
Molecules of Life Chapter 2 Part 1
89

Biology Chapter 2 Part 1

Apr 07, 2018

Download

Documents

Grace Cabigao
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 189

Molecules of Life

Chapter 2

Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 289

21 ImpactsIssues

Fear of Frying

All living things consist of the same kinds of

molecules but small differences in the waysthey are put together have big effects on health

Artificial trans fats found in manufactured and

fast foods raise cholesterol and increase risk of

atherosclerosis heart attack and diabetes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 389

Video Fear of frying

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 489

Fear of Frying

Trans fats are made by adding hydrogen atomsto liquid vegetable oils

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 589

Fig 2-1 p 20

trans fatty acid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 689

22 Start With Atoms

All substances consist of atoms

Atom

bull Fundamental building-block particle of matter

Lifersquos unique characteristics start with the

properties of different atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 2: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 289

21 ImpactsIssues

Fear of Frying

All living things consist of the same kinds of

molecules but small differences in the waysthey are put together have big effects on health

Artificial trans fats found in manufactured and

fast foods raise cholesterol and increase risk of

atherosclerosis heart attack and diabetes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 389

Video Fear of frying

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 489

Fear of Frying

Trans fats are made by adding hydrogen atomsto liquid vegetable oils

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 589

Fig 2-1 p 20

trans fatty acid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 689

22 Start With Atoms

All substances consist of atoms

Atom

bull Fundamental building-block particle of matter

Lifersquos unique characteristics start with the

properties of different atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 3: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 389

Video Fear of frying

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 489

Fear of Frying

Trans fats are made by adding hydrogen atomsto liquid vegetable oils

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 589

Fig 2-1 p 20

trans fatty acid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 689

22 Start With Atoms

All substances consist of atoms

Atom

bull Fundamental building-block particle of matter

Lifersquos unique characteristics start with the

properties of different atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 4: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 489

Fear of Frying

Trans fats are made by adding hydrogen atomsto liquid vegetable oils

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 589

Fig 2-1 p 20

trans fatty acid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 689

22 Start With Atoms

All substances consist of atoms

Atom

bull Fundamental building-block particle of matter

Lifersquos unique characteristics start with the

properties of different atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 5: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 589

Fig 2-1 p 20

trans fatty acid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 689

22 Start With Atoms

All substances consist of atoms

Atom

bull Fundamental building-block particle of matter

Lifersquos unique characteristics start with the

properties of different atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 6: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 689

22 Start With Atoms

All substances consist of atoms

Atom

bull Fundamental building-block particle of matter

Lifersquos unique characteristics start with the

properties of different atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 7: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 789

Subatomic Particles and Their Charge

Atoms consist of electrons moving around anucleus of protons and neutrons

Electron (e-

) bull Negatively charged subatomic particle that

occupies orbitals around the atomic nucleus

Charge

bull Electrical property of some subatomic particles

bull Opposite charges attract like charges repel

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 8: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 889

Subatomic Particles in the Nucleus

Nucleusbull Core of an atom occupied by protons and

neutrons

Proton (p+)bull Positively charged subatomic particle found in the

nucleus of all atoms

Neutronbull Uncharged subatomic particle found in the atomic

nucleus

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 9: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 989

An Atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 10: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1089Fig 2-2a p 21

an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 11: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1189

Elements Different Types of Atoms

Atoms differ in numbers of subatomic particles

Elementbull A pure substance that consists only of atoms with

the same number of protons

Atomic number

bull Number of protons in the atomic nucleus

bull Determines the element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 12: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1289

Elements in Living Things

The proportions of different elements differ

between living and nonliving things

Some atoms such as carbon are found in

greater proportions in molecules made only by

living things ndash the molecules of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 13: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1389

Same Elements Different Forms

Isotopes

bull Forms of an element that differ in the number of

neutrons their atoms carry

bull Changes the mass number but not the charge

Mass number

bull Total number of protons and neutrons in thenucleus of an elementrsquos atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 14: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1489

Radioactive Isotopes

Radioisotope

bull Isotope with an unstable nucleus such as

carbon 14 (

14

C)

Radioactive decay

bull Process by which atoms of a radioisotope

spontaneously emit energy and subatomicparticles when their nucleus disintegrates

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 15: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1589

Carbon 14 A Radioisotope

Most carbon atoms have 6 protons and 6

neutrons (12C)

Carbon 14 (14C) is a radioisotope with six protons

and eight neutrons

When 14C decays one neutron splits into a

proton and an electron and the atom becomes a

different element ndash nitrogen 14 (14N)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 16: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1689

Radioactive Tracers

Researchers introduce radioisotope tracers into

living organisms to study the way they move

through a system

Tracers

bull Molecules with a detectable substance attached

often a radioisotope

bull Used in research and clinical testing

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 17: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1789

Why Electrons Matter

Electrons travel around the nucleus in different

orbitals (shells) ndash atoms with vacancies in their

outer shells tend to interact with other atoms

bull Atoms get rid of vacancies by gaining or losing

electrons or sharing electrons with other atoms

Shell modelbull Model of electron distribution in an atom

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 18: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1889

Shell Models

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 19: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 1989Fig 2-3 (top) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 20: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2089Fig 2-3 (a-c) p 22

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 21: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2189Fig 2-3 (a-c) p

1 proton 1 2

1 electronfirst shell hydrogen (H) helium (He)

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 22: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2289Fig 2-3 (a-c) p

Stepped Art

1 proton 1 2

1 electron

first shell hydrogen (H) helium (He)

A) The first shell corresponds to

the first energy level and it can

hold up to 2 electrons Hydrogen

has one proton so it has one

vacancy A helium atom has 2

protons and no vacancies The

number of protons in each shellmodel is shown

6 8 10

second shell carbon (C) oxygen (O) neon (Ne)

B) The second shell corresponds

to the second energy level and it

can hold up to 8 electrons Carbon

has 6 protons so its first shell is

full Its second shell has 4

electrons and four vacancies

Oxygen has 8 protons and two

vacancies Neon has 10 protons

and no vacancies

11 17 18

third shell sodium (Na) chlorine (Cl) argon (Ar)

C) The third shell which

corresponds to the third energylevel can hold up to 8 electrons

for a total of 18 A sodium atom

has 11 protons so its first two

shells are full the third shell has

one electron Thus sodium has

seven vacancies Chlorine has 17

protons and one vacancy Argon

has 18 protons and no vacancies

A i ti Sh ll d l f

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 23: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2389

Animation Shell models of common

elements

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 24: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2489

Ions

The negative charge of an electron balances the

positive charge of a proton in the nucleus

Changing the number of electrons may fill its

outer shell but changes the charge of the atom

Ion

bull Atom that carries a charge because it has an

unequal number of protons and electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 25: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2589

Ion Formation

electron Chl i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 26: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2689

Fig 2-4 p 23

electron

loss

Sodiumatom

1111p+

11e ndash

charge 0

Sodiumion

11p+11

charge +110e

ndash

electron

gainChlorineatom

17 17p+

17e ndash

charge 0

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 27: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2789

Fig 2-4a p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 28: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2889

Fig 2-4a p 23

electron

gain Chlorine

atom

17 17p+

17e ndash

charge 0

Chloride

ion

18e ndash1717p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 29: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 2989

Fig 2-4b p 23

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 30: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3089

Fig 2-4b p 23

electron

loss Sodium

atom

11 11p+

11e ndash

charge 0

Sodium

ion

11p+11

charge +1

10e ndash

Chlorineelectron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 31: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3189

Fig 2-4 p 23

Sodiumatom

1111p+

11e ndash

charge 0

electron

loss

Sodiumion

11p+11

charge +110e

ndash

Stepped Art

Chlorineatom

17 17p+

17e ndash

charge 0

electron

gain

Chlorideion

18e ndash

17 17p+

charge ndash1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 32: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3289

Animation How atoms bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 33: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3389

Animation PET scan

Animation The shell model of electron

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 34: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3489

Animation The shell model of electron

distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 35: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3589

Animation Subatomic particles

Animation Atomic number mass

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 36: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3689

Animation Atomic number mass

number

Animation Electron arrangements in

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 37: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3789

Animation Electron arrangements in

atoms

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 38: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3889

Animation Isotopes of hydrogen

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 39: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 3989

Video ABC News Nuclear Energy

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 40: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4089

Animation Electron distribution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 41: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4189

23 From Atoms to Molecules

Atoms can also fill their vacancies by sharing

electrons with other atoms

A chemical bond forms when the electrons of

two atoms interact

Chemical bond

bull An attractive force that arises between two atoms

when their electrons interact

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 42: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4289

From Atoms to Molecules

Molecule

bull

Group of two or more atoms joined by chemicalbonds

Compound

bull Type of molecule that has atoms of more than

one element

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 43: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4389

Referring to a Molecule

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 44: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4489

Same Materials Different Results

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 45: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4589

Animation Building blocks of life

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 46: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4689

Ionic Bonds and Covalent Bonds

Depending on the atoms a chemical bond may

be ionic or covalent

Ionic bond

bull A strong mutual attraction formed between ions of

opposite charge

Covalent bond

bull Two atoms sharing a pair of electrons

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 47: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4789

An Ionic Bond Sodium Chloride

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 48: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4889

p 24

ionic bond

11 17

sodium ion (Na+) chloride ion (Cl ndash)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 49: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 4989

Covalent Bonds

Molecular hydrogen (HmdashH) and molecular oxygen (O=O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 50: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5089

p 24

1 1

molecular hydrogen (H2)

8 8

molecular oxygen (O2)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 51: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5189

Polarity

A covalent bond is nonpolar if electrons are

shared equally and polar if the sharing is unequal

Polarity

bull Any separation of charge into distinct positive and

negative regions

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 52: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5289

Polar and Nonpolar Covalent Bonds

Nonpolar

bull Having an even distribution of charge

bull When atoms in a covalent bond share electrons

equally the bond is nonpolar

Polar

bull Having an uneven distribution of chargebull When the atoms share electrons unequally the

bond is polar

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 53: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5389

Importance of Polar Molecules

A water molecule (H-O-H) has two polar

covalent bonds ndash the oxygen is slightly negative

and the hydrogens are slightly positive ndash which

allows water to form hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 54: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5489

p 25

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 55: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5589

p 25

1 8 1

water (H2O)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 56: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5689

Hydrogen Bonds

Hydrogen bond

bull Attraction that forms between a covalently

bonded hydrogen atom and another atom taking

part in a separate covalent bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 57: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5789

p 25

hydrogen bond

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 58: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5889

Importance of Hydrogen Bonds

Hydrogen bonds form and break more easily

than covalent or ionic bonds ndash they do not form

molecules

Hydrogen bonds impart unique properties to

substances such as water and hold moleculessuch as DNA in their characteristic shapes

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 59: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 5989

Animation Ionic bonding

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 60: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6089

Animation Examples of hydrogen bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 61: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6189

Video ABC News Fuel Cell Vehicles

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 62: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6289

Animation Sucrose synthesis

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 63: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6389

Animation Covalent bonds

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 64: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6489

24 Water

All living organisms are mostly water and all

chemical reactions of life are carried out in water

Hydrogen bonds between water molecules give

water unique properties that make life possible

bull Capacity to dissolve many substances

bull Cohesion (surface tension)

bull Temperature stability

Polarity and the

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 65: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6589

Unique Properties of Water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 66: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 67: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6789

Fig 2-7a p 26

slight negative charge

slight positive charge slight positive charge

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 68: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6889

Fig 2-7b p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 69: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 6989

Fig 2-7c p 26

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 70: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7089

Animation Structure of water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 71: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7189

Water and Solutions

Polar water molecules hydrogen-bond to other

polar (hydrophilic) substances and repel

nonpolar (hydrophobic) substances

Hydrophilic (water-loving)

bull A substance that dissolves easily in water

Hydrophobic (water-dreading)

bull A substance that resists dissolving in water

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 72: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7289

Water and Solutions

Water is an excellent solvent

Solventbull Liquid that can dissolve other substances

Solute

bull A dissolved substance

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 73: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7389

Water and Solutions

Salts sugars and many polar molecules

dissolve easily in water

Salt

bull Compound that dissolves easily in water and

releases ions other than H+ and OH-

bull Example sodium chloride (NaCl)

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 74: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7489

Water and Solutions

Water molecules surround the atoms of an ionicsolid and pull them apart dissolving it

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 75: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7589

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 76: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7689

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 77: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7789

Cohesion

Cohesion helps sustain multicelled bodies and

resists evaporation

Cohesion

bull Tendency of water molecules to stick together

Evaporation

bull Transition of liquid to gas

bull Absorbs heat energy (cooling effect)

2 A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 78: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7889

25 Acids and Bases

Water molecules separate into hydrogen ions(H+) and hydroxide ions (OH-)

pH

bull A measure of the number of hydrogen ions (H+) in

a solution

bull The more hydrogen ions the lower the pH

Pure water has neutral pH (pH=7)

bull Number of H+ ions = OH- ions

A id d B

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 79: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 7989

Acids and Bases

Acid

bull Substance that releases hydrogen ions in water

bull pH less than 7

Base

bull Substance that releases hydroxide ions (accepts

hydrogen ions) in water

bull pH greater than 7

A H S l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 80: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8089

A pH Scale

mdash 0 battery acid

mdash 1 gastric fluid

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 81: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8189

Fig 2-9 p 27

g

lemon juicemdash 2acid rain

cola

mdash 3vinegar

more

acid

ic

tomatoeswine

orange juice

mdash 4 bananas

beer

mdash 5 black coffeebread

urine tea typical rain

butter mdash 6 corn

milk

mdash 7pure water

mdash 8 seawater egg whiteblood tears

mdash 9 detergentsbaking soda

Tums

mdash 10hand soaptoothpaste

milk of magnesia

household ammoniamdash 11

morebas

ic

mdash 12 hair remover

bleachmdash 13

mdash 14 drain cleaner

oven cleaner

A i ti Th H l

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 82: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8289

Animation The pH scale

A id R i

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 83: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8389

Acid Rain

Sulfur dioxide and other airborne pollutantsdissolve in water vapor to form acid rain

B ff S t

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 84: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8489

Buffer Systems

Most molecules of life work only within a narrowrange of pH ndash essential for homeostasis

Buffers keep solutions in cells and tissues withina consistent range of pH

Buffer bull Set of chemicals that can keep the pH of a

solution stable by alternately donating andaccepting ions that contribute to pH

CO and the Bicarbonate Buffer System

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 85: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8589

CO2 and the Bicarbonate Buffer System

CO2forms carbonic acid in water

bull CO2+ H

2O rarr H

2CO

3(carbonic acid)

Bicarbonate buffer system

bull Excess H+ combines with bicarbonate

bull H+ + HCO3

- (bicarbonate) harr H2CO

3

Vid ABC N B ttl B kl h

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 86: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8689

Video ABC News Bottle Backlash

Video ABC News Water Use

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 87: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8789

Video ABC News Water Use

Video ABC News Water Wars

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 88: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8889

Video ABC News Water Wars

3D Animation Dissolution

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution

Page 89: Biology Chapter 2 Part 1

862019 Biology Chapter 2 Part 1

httpslidepdfcomreaderfullbiology-chapter-2-part-1 8989

3D Animation Dissolution