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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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