General Chemistry - Kittisak Choojun - Home · General Chemistry 2 ... Chemistry: An Introduction to General, Organic, and Biological Chemistry. Prentice Hall 2014, English 12th ed.

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General Chemistry เคมท วไป 05106030

Industrial Chemistry

General Chemistry

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Lecturer

Dr. Kittisak Choojun

Office: 502, 5th Floor, Science Building

Email : [email protected]

Facebook: Kittisak Chem Kmitl

Office Hour: by appointment

Website: www.kittisakchoojun.com

Online Learning: klix.kmitl.ac.th “General Chemistry”

Email Contact Form

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Topic Always Start with “[Gen Chem Sci]………………”

Example: [Gen Chem Sci] สอบถามเรองการเขาเรยน

Body Please include your name and section.

Email : [email protected]

Online Contact Group

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Drop message on “www.kittisakchoojun.com”

Facebook: Kittisak Chem Kmitl

Online Quizzes, Videos, and related information will be posted

on www.kittisakchoojun.com and klix.kmitl.ac.th

Online Learning and some test will be in “klix.kmitl.ac.th”

Books

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Steven S Zumdahl, Donald J DeCoste. Introductory

Chemistry: A Foundation. Thomson Brooks/Cole 2010.

English 7th ed.

Karen C. Timberlake. Chemistry: An

Introduction to General, Organic, and

Biological Chemistry. Prentice Hall 2014,

English 12th ed.

Theodore E. Brown, H. Eugene H LeMay, Bruce E.

Bursten, Catherine Murphy, Patrick Woodward.

Chemistry: The Central Science. Prentice Hall 2011,

English 12th ed.

Ralph H. Petrucci, F. Geoffrey Herring, Jeffry D. Madura, Carey

Bissonnette. General Chemistry: Principles and Modern

Applications. Prentice Hall 2010, English 10th ed.

Books

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Raymond Chang and Jason Overby. General

Chemistry: The Essential Concepts. McGraw-

Hill Science/Engineering/Math 2010, 6th ed.

สามารถใชเอกสารและหนงสอเคมทวไปไดทกสถาบน

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Week Date Chapter Topic Learning Lecturer

1 5-9 Aug 1 Atomic Structure In class Dr.Kittisak

2 12-16 Aug 1 Atomic Structure In class Dr.Kittisak

3 19-23 Aug 2 Periodic Table Online Dr.Kittisak

4 26-30 Aug 3 Chemical Bonding In class Dr.Kittisak

5 2-6 Sep 3 Chemical Bonding In class Dr.Kittisak

6 9-13 Sep 4 Stoichiometry Online Dr.Kittisak

7 16-20 Sep 5 Liquid and Solution Online Dr.Kittisak

- 23-27 Sep Midterm Midterm Midterm Midterm

8 30Sep-4Oct 6 Solids In class Dr.Kittisak

9 7-11 Oct 7 Gases In class Dr.Kittisak

10 14-18 Oct 7 Gases In class Dr.Kittisak

11 21-25 Oct 8 Thermochemistry In class Dr.Kittisak

12 28Oct-1Nov 9 Kinetics In class Dr.Kittisak

13 4-8 Nov 10 Equilibrium In class Dr.Kittisak

14 11-15 Nov 11 Acids and Bases In class Dr.Kittisak

15 18-22 Nov 11 Acids and Bases In class Dr.Kittisak

16 25-29 Nov Review In class Dr.Kittisak

2-6 Dec Final Final Final Final

9-13 Dec Final Final Fian Final

Scores

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Exam Score (%)

Midterm 35

Online Quiz and Class Activity 30

Final 35

Midterm and Final

Multiple choices + Writing Exam

Self Studying

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Significant Figures .

Measurement and numbers

This will definitely be on the quizzes.

Atoms and Electronic Structure of Atoms

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Ref: Ralph H. Petrucci, F. Geoffrey Herring, Jeffry D. Madura, Carey Bissonnette. General Chemistry:

Principles and Modern Applications. Prentice Hall 2010, English 10th ed.

Theodore E. Brown, H. Eugene H LeMay, Bruce E. Bursten, Catherine Murphy, Patrick Woodward.

Chemistry: The Central Science. Prentice Hall 2011, English 12th ed.

Raymond Chang and Jason Overby. General Chemistry: The Essential Concepts. McGraw-Hill

Science/Engineering/Math 2010, 6th ed.

The Atomic Theory of Matter

Greek – Atomos meaning “indivisible or uncuttable”

Plato and Aristotle --- “Atomic”

In Europe during the 17th century --- “Atoms”

Dalton proposed the atomic theory.

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Dalton’s Atomic Theory

1. สสารทกชนดประกอบดวยสวนทเลกทสดเรยก “อะตอม”

2. อะตอมของธาตชนดเดยวกน ยอมมน าหนกเทากน มสมบตเหมอนกน แตขนาดลกษณะและน าหนกจะแตกตางกบอะตอมของธาตอน

3. อะตอมไมอาจท าใหเกดขน ท าลายยอยใหเลกลงหรอเปลยนเปนอะตอมอน

4. สารประกอบเกดจากการรวมตวทางเคมของธาตในอตราสวนลงตวนอยๆ

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The Discovery of Atomic Structure

Fact to keep in mind: Particles with the same charge repel one another, whereas particles with unlike charge attract one another.

Cathode Rays and Electrons

During the mid 18th century, scientists began to study electrical discharge through a glass tube pumped almost empty of air.

http://www.youtube.com/watch?v=CsjLYLW_3G0

http://www.youtube.com/watch?v=O9Goyscbazk

http://www.youtube.com/watch?v=2xKZRpAsWL8

http://www.youtube.com/watch?v=JUJPyQtoB5E

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Basic Concept Between Electrically Charged Objects

(a) Electrostatically charged comb. If you comb your hair on a dry day, a static charge develops on the comb and causes bits of paper to be attracted to the comb. (b) Both objects on the left carry a negative electric charge. Objects with like charge repel each other. The objects in the center lack any electric charge and exert no forces on eachother. The objects on the right carry opposite charges one positive and one negative and attract each other.

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Cathode Rays and Electrons

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Cathode Rays and Electrons

The British scientist J. J. Thomson (1856-1940) observed that cathode rays are the same regardless of the identity of the cathode material.

In a paper published in 1897, Thomson described cathode rays as streams of negatively charged particles.

The discovery of what became known as the electron.

The ratio of the electron’s electrical charge to its mass is 1.76 x 108 coulombs per gram.

Noble Prize in Physics in 1906

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J. J. Thomson’s Plum Pudding Model of the Atom

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The plum-pudding atomic model

According to this model, a helium atom would have a +2 cloud of positive chargeand two electrons (-2). If a helium atom loses one electron, it becomes charged and is called an ion. This ion, referred to as He+

has a net charge of +1. If the helium atom loses both electrons, the He2+ ion forms.

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Charge of the Electron

Robert Millikan (1868 – 1953) from the University of Chicago succeeded in measuring the charge of an electron.

The charge of an electron is 1.602 x 10-19 C

So from Thomson’s charge-to-mass ratio, 1.76 x 108

C/g

https://www.youtube.com/watch?v=XMfYHag7Liw

https://www.youtube.com/watch?v=UFiPWv03f6g

Noble Prize in Physics in 1923

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Milikan Oil Drop Experiment

Robert Millikan (1868 – 1953) from the University of Chicago succeeded in measuring the charge of an electron.

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Radioactivity

In 1896 Henri Becquerel (French scientist) discovered that a

compound of uranium spontaneously emits high-energy radiation

called radioactivity.

Marie Curie and Pierre (her husband) began experiments to

isolate the radioactive components of the compound.

Ernest Rutherford revealed three types of radiation: alpha, beta,

and gamma.

http://www.youtube.com/watch?v=hqofR3MXax4

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Ernest Rutherford, 1st Baron

Rutherford of Nelson

Noble Prize in Chemistry 1908

http://www.youtube.com/watch?v=ec8iomUS34U

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Rutherford’s α–scattering Experiment

ยงรงสแอลฟา (ประจ +2) พบวารงสสวนใหญ (>99%)ผานไปไดโดยไมเบยงเบน มนอยมากทเบยงเบนและสะทอนกลบ

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The Nuclear Model of the Atom

Rutherford explained the results by postulating the nuclear model

of the atom, a model in which most of the mass of each gold atom and

all of its positive charge reside in a very small, extremely dense region

that he called the nucleus.

Rutherford discovered protons and James Chadwick discovered

neutrons.

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The Nuclear Atom Illustrated by the Helium Atom

In this drawing, electrons are shown much closer to the nucleus than is the case. The actual situation is more like this: If the entire atom were represented by a room, 5m x 5m x 5m, the nucleus would occupy only about as much space as the period at the end of this sentence.

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Electronic Structure of Atoms The Wave Nature of Light

Electromagnetic radiation carries

energy through space, it is also known as

radiant energy.

All types of electromagnetic radiation move

through a vacuum at 3.00 x 108 m/s, the

speed of light.

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Electromagnetic WavesThis sketch of two different

electromagnetic waves shows the

propagation of mutually

perpendicular oscillating electric

and magnetic fields. For a given

wave, the wavelengths,

frequencies, and amplitudes of

the electric and magnetic field

components are identical. If

these views are of the same

instant of time, we would say

that (a) has the longer

wavelength and lower frequency,

and (b) has the shorter

wavelength and higher

frequency

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The Wave Nature of Light

The yellow light given off by a sodium vapor lamp used for public lighting

has a wavelength of 590 nm. What is the frequency of this radiation?

A laser used in eye surgery to fuse detached retinas produces radiation

with a wavelength of 645.0 nm. Calculate the frequency of this radiation.

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Quantized Energy and Photons

There are some puzzles that wave model cannot explain:

1. The emission of light from hot objects referred to as blackbody

radiation because the objects studied appear black before heating.

2. The emission of electrons from metal surfaces on which light

shines –the photoelectric effect

3. The emission of light from electronically excited gas atoms –

emission spectra

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Hot Objects and the Quantization of Energy

The relationship between the temperature and

the intensity and wavelength of the emitted

radiation.

German physicist named Max Planck solved the

problem by assuming that energy can be either

released or absorbed by atoms only in discrete

“chunks” of some minimum size named

“quantum” (fixed amount).

6.626 x 10-34 J s33

Sources for Light Emission

Light emitted by an electric discharge through (a) hydrogen gas and (b) neon gas. Light emitted when compounds of the alkali metals are excited in the gas flames: (c) lithium, (d) sodium, and (e) potassium.

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The Photoelectric effect and Photons

A minimum frequency of light, different

for different metals, is required for the

emission of electrons.

Cesium --- light with a frequency of 4.60

x 1014 s-1 or greater causes the emission of

electrons.

Albert Einstein used Plank’s theory to

explain the photoelectric effect.

Einstein assumed that the radiant energy

striking the metal surface behaves like a

stream of tiny energy packets, which is like

a “particle” of energy, is called a photon.

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A laser emits light that has a frequency of 4.69 x 1014 s-1. What is the energy of one photon of this radiation?

If the laser emits a pulse containing 5.0 x 1017 photons of this radiation, what is the total energy of that pulse?

If the laser emits 1.3 x 10-2 J of energy during a pulse, how many photons are emitted?

http://www.youtube.com/watch?v=kcSYV8bJox8http://www.youtube.com/watch?v=ubkNGwu_66s

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Line Spectra and the Bohr Model

Line Spectra

Monochromatic -- a laser

Polychromatic --- bulbs, stars

Continuous spectrum

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Line Spectrum

Johann Balmer, a Swiss schoolteacher, showed that the wavelengths of these four lines fit an intriguingly simple formula that relates the wavelengths to integers.

Later, the additional lines were found in UV and IR regions. So, Balmer’s equation was extended to a more general one called the “ Rydberg equation.”

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Rydberg Equation

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Bohr’s Model Niels Bohr (Danish Physicist)

assumed that electrons in hydrogen atoms move in circular orbits around the nucleus.

Though, how can it not be attracted to the nucleus then?

Bohr approached this problem in much the same way that Planck had approached the problem of the nature of the radiation emitted by hot objects.

He assumed that the prevailing laws of physics were inadequate to describe all aspects of atoms.

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Bohr’s Model

As the electron moves around the

nucleus, it is constantly changing

direction.

Forces acting on an electron moving

in a hydrogen atom.

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Bohr’s Model

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Bohr’s Model Three Postulates:

1. Only orbits of certain radii,

corresponding to certain specific

energies, are permitted for the

electron in a hydrogen atom.

2. An electron in a permitted orbits is

in an “allowed” energy state. An

electron in an allowed energy state

does not radiate energy and, therefore,

does not spiral into the nucleus.

3. Energy is emitted or absorbed by the

electron only as the electron changes

from one allowed energy state to

another. This energy is emitted or

adsorbed as a photon that has energy

E = hv.

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The Energy States of the Hydrogen Atom

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Energy-Level Diagram for the Hydrogen Atom

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Limitations of the Bohr Model

It cannot explain the spectra of other atoms.

Questioning about the negatively charged of electron would not

just fall into the positively charged nucleus!

The most Significant about Bohr’s Model :

Electrons exist only in certain discrete energy levels, which are

described by quantum numbers.

Energy is involved in the transition of an electron from one level to

another.

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The Wave Behavior of Matter

The dual nature of radiant energy (a wave-like and a particle-like (photon))

became more familiar concept after Bohr’s model had been introduced.

Louis de Broglie suggested that an electron moving about the nucleus of an

atom behaves like a wave and therefore has a wavelength. He proposed:

m = mass, v = velocity

mv = momentum.

h = Planck’s constant

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The Uncertainty Principle

Heisenberg’s principle

It is impossible for us to know simultaneously both the exact

momentum of the electron and its exact location in space.

Note: Give it a thought! Electron has a mass of 9.11 x 10-31 kg, moves

at an average speed of about 5 x 106 m/s. 1% uncertainty, calculate the

uncertainty in the position in the position of the electron.

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= wave function

is just a function in mathematics but

2 is the probability to find the electron (electron density)

H = Hamiltonian (operator)

Quantum Mechanics and Atomic Orbitals

In 1926, the Austrian physicist Erwin

Schrodinger, using a complicated

mathematical technique, formulated an

equation that describes the behavior and

energies of submicoroscopic particles in

general, an equation analogous to Newton’s

laws of motion for macroscopic objects.

“Schrodinger equation” Erwin SchrÖdinger

(1887-1961)

Austrian physicist

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Classical-mechanical observable variables and

their corresponding quantum-mechanical

operators

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Example of Quantum Mechanics

Energy of Electrons

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The Quantum Mechanical Description of the

Hydrogen Atom

Electron density gives the probability

that an electron will be found in a

particular region of an atom.

This is not the orbit like Bohr’s model.

“An atomic orbital” can be thought of as

the wave function of an electron in an

atom.

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Quantum Numbers

In quantum mechanics, three quantum numbers are required

to describe the distribution of electrons in hydrogen and

other atoms.

Principal quantum number

Angular momentum quantum number

Magnetic quantum number.

Spin quantum number is the fourth which describes the

behavior of a specific electron and completes the description of

electrons in atoms.

Describing atomic

orbitals and

labeling electrons

that reside in them

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Quantum Number

The Principal Quantum Number (n)

Integral values 1, 2, 3,….

Determining the energy of an orbital

The larger n is the greater the average distance of an electron in

the orbital from the nucleus.

The Angular Momentum Quantum Number (l)

Representing the “shape” of the orbitals

Integral values from 0,…, (n-1)

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Quantum Number

The Magnetic Quantum Number (ml)

Describing the orientation of the orbital in

space

The Electron Spin Quantum Number (ms)

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Atomic Orbitals

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Shells and subshells of a hydrogen atom. The hydrogen atom orbitals are organized into shells and subshells.61

s-Orbital

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p-Orbitals

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d-Orbitals

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d-Orbitals

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Penetration and Shielding

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