Chemistry Chapter 2

Coloring the Periodic Table - Families

Chemistry Chapter 2Matter and Change

Chemistry is

the study of the composition, structure, and properties of matter and the changes it undergoes

C2H5OH + 3 O2 2 CO2 + 3 H2O + Energy Reactants ProductsMatterAnything that has mass and occupies space.The stuff we are made up of.MassA measure of the amount of matter.How much stuff is there.

AtomThe smallest unit of an element that maintainsthe properties of that elementElement-A pure substance made of only one kind of atom-There are 115 elements on the periodic table.-88 occur naturally.

CompoundA substance that is made from the atoms of two or more elements that are chemically bonded.Example -Sucrose C12H22O11

Sucrose is also known as table sugar, and is used to make Gummy Bears!

Properties of Matter Extensive Properties - depend on the amount of matter that is present.Examples - Volume, Mass, Energy Content (think calories!) Intensive Properties - Do not depend on the amount of matter present.Examples Melting point, Boiling Point,Density Properties of MatterPhysical Properties Characteristics that can change without becoming a different substanceExamples odor, color, physical stateChemical Properties its ability to form a new substance.Examples Wood burning, Rusting of steel, Digestion of food Chemical ChangeA change in which one or more substances are converted into different substances.This is on an atomic level.Heat and light are often evidence of a chemical change.

Physical ChangeA change in a substance that does not involve a change in the identity of the substance.Example:Phase Changes

MixturesAnything substance with a variable composition.EX.WoodSodaCoffeeair-contains only a single element or compoundEX. Gold ringdistilled water

NOT EXAMPLES: water from the tap, sodaPure SubstanceHomogeneous Mixtures-same through outEX. Sea water, plastic cupHeterogeneous Mixtures-has areas with different propertiesEX. Wood, bucket of sand and waterClassification of Matter

States of MatterMatter can take forms/statesWhat are they?How do solids behave?The particles of a solid are very tightly packed and move slightly (vibrate).Definite shape Definite Volume

How do liquids behave?Particles in a liquid can slide past each otherIndefinite shape takes shape of containerDefinite volume

How do gases behave?Particles in a gas can move about freelyIndefinite shape Indefinite volume

How does plasma behave?Particles in plasma are broken (charged particles)Indefinite shape Indefinite volumeConduct electricity

Phase DifferencesSolid definite volume and shape; particles packed in fixed positions.Liquid definite volume but indefinite shape; particles close together but not in fixed positionsGas neither definite volume nor definite shape; particles are at great distances from one another

Plasma high temperature, ionized phase of matter as found on the sun.Copper Phases - Solid

Copper Phases - Liquid

Copper Phases Vapor (gas)

States of Matter Graphic Organizer!For each of the states of Matter complete this information:StateDefinitionProximity (how close the particles are to eachother)Movement of the particlesThree examples

Properties of Metals Metals are good conductors of heat and electricity Metals are malleable (can be hammered into thin sheets) Metals are ductile (can be pulled into wires)Metals have luster (shiny)

Examples of Metals

Potassium, K reacts with water and must be stored in kerosene or oil Zinc, Zn, is more stable than potassium

Copper, Cu, is a relatively soft metal, and a very good electrical conductor.Mercury, Hg, is the only metal that exists as a liquid at room temperatureProperties of Nonmetals

Carbon, the graphite in pencil lead is a great example of a nonmetallic element. Nonmetals are poor conductors of heat and electricity Nonmetals tend to be brittle Nonmetals do not have luster Many nonmetals are gases at room temperatureExamples of Nonmetals

Sulfur, S, was once known as brimstoneMicrospheres of phosphorus, P, a reactive nonmetal Graphite is not the only pure form of carbon, C. Diamond is also carbon; the color comes from impurities caught within the crystal structureProperties of MetalloidsMetalloids straddle the border between metals and nonmetals on the periodic table. They have properties of both metals and nonmetals.Metalloids are more brittle than metals, less brittle than most nonmetallic solids Metalloids are semiconductors of electricity Some metalloids possess metallic luster

Silicon, Si A Metalloid

Silicon has metallic luster Silicon is brittle like a nonmetal Silicon is a semiconductor of electricity

Other metalloids include: Boron, B Germanium, Ge Arsenic, As Antimony, Sb Tellurium, Te

The Periodic TablePeriodGroup or family

PeriodGroup or FamilyDescribe how to read the periodic table:Every table has:

Describe how to read the periodic table:Atomic Symbol:One or two letters chosen to represent an element.These symbols are used every where in the worldUsually, abbreviation of the element or the abbreviated Latin name of the element.

Describe how to read the periodic table:Atomic Number

The number of protons in an atom identifies the element.

Describe how to read the periodic table:Atomic Mass:The average mass of an elementMeasured in atomic mass units ("amu)Is an average of all the isotopes of an element.

Mass Number:protons + neutrons = Mass NumberIs always a whole number.Atomic Structure

What are the 3 major parts of an atom?Proton Neutron ElectronThe NucleusThe central part of an atomComposed of protons and neutronsContains most of an atom's massDiscovered by Ernest Rutherford in 1911.ProtonsPositively charged particles found in the atomic nucleus. Have a mass of 1 AMUAre made from other particles called quarks.

NeutronsUncharged particles found in the atomic nucleusHave a mass of 1 AMUMade from other particles called quarks.

ElectronNegatively charged particles that surround the atom's nucleus. Have no mass??Determine properties of the atom. Chemical reactions involve sharing or exchanging electrons.

Draw a Diagram of an Atom

A diagram showing the location of each part of the atom.

Atomic SymbolsSome show the mass number and atomic number in nuclear symbol formmass number 23 Na atomic number 11

IsotopesAtoms that have the same number of protons but different numbers of neutrons Describe IsotopeExample:

http://education.jlab.org/glossary/isotope.html Naturally occurring carbon consists of three isotopes, 12C, 13C, and 14C. State the number of protons, neutrons, and electrons in each of these carbon atoms. 12C 13C14C 6 6 6#p+ _______ _______ _______ #no _______ _______ _______ #e- _______ _______ _______

Answers12C 13C14C 6 6 6#p+ 6 6 6 #no 6 7 8 #e- 6 6 6

Some quick questionsAn atom has 14 protons and 20 neutrons.A.Its atomic number is1) 142) 163) 34

B. Its mass number is1) 142) 163) 34

C. The element is1) Si2) Ca3) Se

D.Another isotope of this element is1) 34X 2) 34X 3) 36X 16 14 14

IONS

IONS are atoms or groups of atoms with a positive or negative charge. Taking away an electron from an atom gives a CATION with a positive chargeAdding an electron to an atom gives an ANION with a negative charge.To tell the difference between an atom and an ion, look to see if there is a charge in the superscript! Examples: Na+ Ca+2 I- O-2PREDICTING ION CHARGESIn generalmetals (Mg) lose electrons ---> cationsnonmetals (F) gain electrons ---> anionsLearning Check CountingState the number of protons, neutrons, and electrons in each of these ions. 39 K+ 16O -241Ca +2 19 8 20#p+ ___________________ #no ___________________#e- ___________________