Welcome to CHEMISTRY !!!

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Welcome to CHEMISTRY !!!

• An Observational Science
• An Experimental Science
• A Laboratory Science
• An Interesting Science
• An Important Science
• A Hard Science

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What Happened To The Balloon?

• It was Whimpy and Broke!
• It was fearful of all of the people!
• Zoller scared it!
• It got zapped by Klingons!
• Hydrogen burns!

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2H2 (g) O2 (g) 2 H2O (g) Energy

• Hydrogen and oxygen are diatomic gases!
• Water can be a gas!
• ENERGY was given off!-- This is characteristic of
  an Exothermic Reaction!
• This is a balanced chemical reaction!

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CHEMISTRY
The Study of Matter and its Properties, the
Changes that Matter Undergoes, and the
Energy Associated with those Changes
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Chemistry as the Central Science
Atmospheric Sciences
Physics
Oceanography
Medicine
Economics
Governments
Chemistry
People
Geology
Biology
Politics
Astronomy
Anthropology
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Chemistry Homework !!!
Chemistry is not a spectator sport, you must
become involved, and that means that you must do
homework!
Linus Pauling - 1967
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Student versus Class Computer Notes
Student notes will have answers missing, and you
will have to fill Them in during or before
class! Class notes will have the answers in them,
so you can copy them down and have the answers.
This requires you, the student to do some writing
during class in addition to the materials that I
write on the overheads. The reason for this is
that you will remember better by using more of
your senses during class time. Calculate the
volume of a cube with sides of 2.0
inches? Student 2.0 in x 2.0 in x 2.0 in
Class notes 2.0 in x 2.0 in x 2.0 in
8.0 in3 Suggestion You do the work before
class, and in that way learn
what is going to be done in class, then check
in class!
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Chemistry 142
Text Chemical Principles
Fifth Edition - By Steven S. Zumdahl
Chapter 1 Chemists and Chemistry Chapter 2
Atoms, Molecules, and Ions Chapter 3
Stoichiometry Mole - Mass Relationships in
Chemical Systems Chapter 21
The Nucleus A Chemists View Chapter 4
Types of Chemical Reactions and
Solution Stoichiometry Chapter 5
Gases Chapter 6 Chemical
Equilibrium Chapter 7 Acids and Bases Chapter
8 Applications of Aqueous Eqilibria
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Chapter 1 Chemists and Chemistry
1.1 Thinking Like a Chemist 1.2 A Real-World
Chemistry Problem Stephanie Burns
Chemist, Executive 1.3 The Scientific Model
Critical Units! 1.4 Industrial Chemistry 1.5
Polyvinyl Chloride (PVC)
Real-World Chemistry
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Chemical technicians check water quality.
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Figure 1.1 Chemists interact
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Chemists at work
Source Photo Researchers
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Acid-damaged paper
Source Fundamental Photos
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Figure 1.2
Paper A Polymer called Cellulose
The Polymer cellulose, which consists of
B-D-glucose monomers
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Figure 1.3 Schematic diagram of the strategy for
solving the problem of the acid decomposition of
paper.
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Artist's conception of the lost Mars Climate
Orbiter.
Source NASA
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Figure 1.4 The various parts of the scientific
method
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Industrial processes require large plants for
production of chemicals.
Source Photo Researchers
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Poly(Vinyl Chloride) (PVC) and Teflon
H H H H H H H H
C C C C C C C C
n
H Cl
H Cl H Cl H Cl H Cl
Vinyl chloride
PVC
F F
F F F F F F F F
C C
C C C C C C C C
n
F F
F F F F F F F F
Teflon
Tetrafluoroethylene
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Scientist inspecting
Source Corbis
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Table 1.1 (P 12) Types of Additives
Commonly Used in the
Production of PVC
Type of Additive
Effect
Plasticizer
Softens the Material Heat stabilizer
Increases resistance to thermal

decomposition Ultraviolet absorber
Prevents damage by sunlight Flame
retardant Lowers
flammability Biocide
Prevents bacterial or fungal attack
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Definitions-I
Matter - The stuff of the universe books,
planets, trees, professors -
anything that has mass and
volume. Composition - The types and amounts of
simpler substances that make up a
sample of matter. Properties - The
characteristics that give each
substance a unique identity. Physical
Properties - are those the substance shows by
itself, without interacting with
another substance ( color,
melting point, boiling point,density, etc.)
Chemical Properties - are those that the
substance shows as it interacts
with, or transforms into, other
substances (flammability, corrosiveness, etc.)
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STATES OF MATTER -and The World around US

• SOLID - The Earth
• LIQUID - Water
• GAS - The Atmosphere

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Energy Involved in Phase Changes
Liberates Energy
Gas
Boiling
Condensation
Liquid
Melting
Freezing
Solid
Requires Energy
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Definitions - II
Energy - The capacity to do work! Potential
Energy - The energy due to the position
of the object.Or Energy
from a chemical
reaction. Kinetic Energy - The energy due to
the motion of the
object.
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Units Used in Calculations
Length A car is 12 feet long, not 12 !
A person is 6 feet
tall, not 6 !
Area A carpet measuring 3 feet(ft) by 4 ft has
an area of ( 3 x 4 )( ft x
ft ) _________ ft2
Speed and Distance A car traveling 350
miles(mi) in
7 hours(hr) has a speed of 350 mi / 7 hr 50
mi / hr
In 3 hours the car travels 3 hr x 50 mi
/ hr ___________ mi
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Derived SI Units
Quantity Definition of Quantity
SI unit
Area Length squared
m2 Volume
Length cubed
m3 Density Mass per unit
volume kg/m3 Speed
Distance traveled per unit time
m/s Acceleration Speed
changed per unit time
m/s2 Force Mass times
acceleration of object kg m/s2

( newton,
N) Pressure Force per unit area
kg/(m2)

( pascal,
Pa) Energy Force times distance
traveled kg m2/s2

( joule, J)
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How to Solve Chemistry Problems
1) Problem States all of the information needed
to solve the Problem. 2)
Plan Clarify the known and unknown.
Suggest the steps needed to find the
solution. Develop
a roadmap solution. 3)Solution Calculations
appear in the same order as outlined. 4) Check
Is the result what you expect or at least in the
same order of magnitude! 5)
CommentAdditional information as needed.
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Conversion Factors Unity Factors - I
Equivalent factors can be turned into conversion
factors by dividing one side into the other!
1 mile 5280 ft or 1 1 mile / 5280 ft
5280 ft / 1 mi
1 in 2.54 cm or 1 1 in / 2.54 cm
2.54 cm / 1 in
In converting one set of units for another, the
one desired is on top in the conversion factor,
and the old one is canceled out!
convert 29,141 ft into miles!
29,141 ft x 1 mi / 5280 ft ______________ mi
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Conversion Factors - II
1.61 km 1 mi or 1 1.61 km / 1 mi
Convert 5.519 miles in to kilometers
5.519 mi x 1.61 km / mi 8.89 km
conversions in the metric system are easy, as 1
km 1000 m and 1 meter (m) 100
centimeters(cm)
and 1 cm 10 millimeters(mm)
Therefore into cm and mm!
8.89 km x 1000m / 1 km 8,890 m 8,890 m x
100 cm / m 889,000 cm
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Conversion Factors - III

• Multiple conversion factors!
• Convert 3.56 lbs/hr into units of milligrams/sec.

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Conversion Factors - IVmetric volume to metric
volume

• 1.35 x 109 km3 volume of worlds oceans
• 1.35 x 109 km3 x (103 m/1 km )3 x ( 103 l/m3)
• 1.35 x 1021 liters
• conversion factors
• 1000m 1km
• 1000 l 1m3

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Calculate the mass of 1.00 ft3 of Lead
(density11.4g/ml)?
Conversion Factors - V

• 1.00 ft3 x (12 in/ft)3 x (2.54 cm/in)3
• 28,316.84659
  cm3
• 2.83 x 104 cm3 x 11.4 g/cm3 322,620.0000 g
• Ans. 3.23 x 105 g ________________ kg

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An Example Problem!
The Volume of an irregularly shaped solid can be
determined from the volume of water it displaces.
A graduated cylinder contains 245.0 ml water.
When a small piece of Pyrite, an ore of Iron, is
submerged in the water, the volume increases
to 315.8 ml. What is the volume of the piece of
Pyrite in cm3 and in liters.
Vol (ml) 315.8 ml - 245.0 ml 70.80 ml
Vol (cm3) 70.80 ml x 1 cm3/ 1 ml 70.80
cm3 Vol (liters) 70.80 ml x 10 -3liters / ml
__________ liters
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Archimedes Principle Problem
Problem Calculate the density of an irregularly
shaped metal object that has a mass of 567.85
g if when it is placed into a 2.00 liter
graduated cylinder containing 900.00 ml of water,
the final volume of the water in the cylinder
is 1,277.56 ml? Plan Calculate the volume from
the different volume readings, and calculate
the density using the mass that was
given. Solution
Volume 1,277.56 ml - 900.00 ml 377.56 ml
mass 567.85 g
Density
_________ g / ml
volume 377.56 ml
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Definitions - Mass Weight
Mass - The quantity of matter an object contains
kilogram - ( kg ) - the SI base unit of mass, is
a platinum -
iridium cylinder kept in
Paris as a standard!
Weight - depends upon an objects mass and the
strength of the gravitational
field pulling on it.
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A Sample Problem - I
International computer communications will soon
be carried by optical fibers in cables laid along
the ocean floor. If one strand of optical fiber
weighs 1.19 x 10 -3 lbs/m, what is the total
mass (in kg) of a cable made of six strands of
optical fiber, each long enough to link New York
and Paris? (8.85 x 103 km).
Mass (kg) of Cable
1 km 103 m
2.205 lb 1 kg
1m 1.19 x 10 -3 lb
6 fibers 1 cable
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Sample Problem - II
Length (m) of Fiber 8.85 x 103 km x 103m / km

8.85 x 106 m Mass (lb) of Fiber
8.85 x 106 m x 1.19 x 10-3 lb / 1m
1.05 x 104
lb Mass (lb) of cable 1.05 x 104 lb / 1 fiber
x 6 fibers / 1 cable
6.30 x 104 lb / cable Mass
(kg) of cable 6.30 x 104 lb / 1 cable x 1kg /
2.205 lb
2.86 x 104 kg / cable
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A Problem on Density - I
Lithium (Li) is a soft, gray solid that has the
lowest density of any metal. If a slab of Li
weighs 1.49 x 103mg and has sides that measure
20.9 mm by 11.1 mm by 12.0 mm, what is the
density of Li in g/ cm3 ?
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Density Problem - II
1 g
Mass (g) of Li 1.49 x 103 mg x
1.49 g Length (cm) of one side 20.9 mm x
1cm / 10 mm 2.09 cm Similarly, the other side
lengths are 1.11 cm and 1.20 cm Volume (cm3)
2.09 cm x 1.11 cm x 1.20 cm 2.78 cm3
Density of Li
___________ g/cm3
103 mg
1.49 g
2.78 cm3
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Like Problem on Density of a Metal
Problem Cesium is the most reactive metal in the
periodic table, what is its density if a
3.4969 kg cube of Cs has sides of 125.00 mm
each? Plan Calculate the volume from the
dimensions of the cube, and calculate the
density from the mass and volume. Solution
length 125.00 mm 12.500 cm
mass 3.4969 kg x 1000g/kg 3,496.9 g
Volume (length)3 (12.500 cm)3 1,953.125 cm3
mass 3496.9 g
density
_________g/ml
volume 1,953.125 cm3
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Temperature Scales and Interconversions
Kelvin ( K ) - The Absolute temperature scale
begins at absolute zero
and only has positive values.
Celsius ( oC ) - The temperature scale used by
science, formally
called centigrade and most
commonly used scale around the world,
water freezes at 0oC, and boils
at 100oC.
Fahrenheit ( oF ) - Commonly used scale in
America for our
weather reports, water freezes at 32oF,
and boils at 212oF.
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Temperature Conversions
T (in K) T (in 0C) 273.15 T (in 0C)
T (in K) - 273.15 T (in 0F) 9/5 T (in
0C) 32 T (in 0C) T (in 0F) - 32 5/9
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Temperature Conversions - I
The boiling point of Liquid Nitrogen is 1950C,
what is the temperature in Kelvin and degrees
Fahrenheit?
T (in K) T (in 0C) 273.15 T (in K)
-195.8 0C 273.15 77.35 K ________
K T (in 0F) 9/5 T (in 0C) 32 T (in
0F) 9/5 ( -195.8 0C) 32 _______________
0F
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Temperature Conversions - II
The normal body temperature is 98.6 0F, what is
it in degrees Celsius and Kelvin?
T (in 0C) T (in 0F) - 32 5/9 T (in 0C)
98.6 0F - 32 5/9 37.0 0C T (in K)
T (in 0C) 273.15 T (in K) 37.0 0C
273.15 _________ K
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Rules for Determining Which Digits Are
Significant
All digits are significant, except zeros that are
used only to position the decimal point.
1. Make sure that the measured quantity has a
decimal point. 2. Start at the left of the number
and move right until you reach the first
nonzero digit. 3. Count that digit and every
digit to its right as significant. Zeros that
end a number and lie either after or before the
decimal point are significant thus 1.030 ml has
four significant figures, and 5300. L has four
significant figures also. Numbers such as 5300 L
is assumed to only have 2 significant figures. A
terminal decimal point is often used to clarify
the situation, but scientific notation is the
best!
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Examples of Significant Digits in Numbers
Number - Sig digits Number
- Sig digits
0.0050 L two 1.34000 x 107
nm six 18.00 g four
5600 ng two 0.00012 kg
two 87,000 L
two 83.0001 L six
78,002.3 ng six 0.006002 g
four 0.000007800 g
four 875,000 oz three 1.089 x
10 -6L four 30,000 kg one
0.0000010048 oz five 5.0000 m3
five 6.67000 kg
six 23,001.00 lbs seven 2.70879000
ml nine 0.000108 g three
1.0008000 kg eight 1,470,000 L
three 1,000,000,000 g one
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Rules for Significant Figures in Answers
1. For multiplication and division. The number
with the least certainty limits the certainty of
the result. therefore, the answer contains the
same number of significant figures as there are
in the measurement with the fewest significant
figures. Multiply the following numbers
9.2 cm x 6.8 cm x 0.3744 cm 23.4225 cm3 23 cm3
2. For addition and subtraction. The answer has
the same number of decimal places as there are
in the measurement with the fewest decimal
places. Example, adding two volumes 83.5 ml
23.28 ml 106.78 ml 106.8 ml Example
subtracting two volumes 865.9 ml -
2.8121393 ml 863.0878607 ml _______ ml
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Rules for Rounding off Numbers
1. If the digit removed is more than 5, the
preceding number increases by 1 5.379 rounds
to 5.38 if three significant figures are retained
and to 5.4 if two significant figures are
retained. 2. If the digit removed is less than 5,
the preceding number is unchanged 0.2413
rounds to 0.241 if three significant figures are
retained and to 0.24 if two significant figures
are retained. 3.If the digit removed is 5, the
preceding number increases by 1 if it is odd and
remains unchanged if it is even 17.75 rounds to
17.8, but 17.65 rounds to 17.6. If the 5 is
followed only by zeros, rule 3 is followed if
the 5 is followed by nonzeros, rule 1 is
followed 17.6500 rounds to 17.6, but 17.6513
rounds to 17.7 4. Be sure to carry two or more
additional significant figures through a
multistep calculation and round off only the
final answer. (In sample problems and follow-up
problems, we round off intermediate steps of a
calculation to show the correct number of
significant figures.)
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Precision and Accuracy Errors in
Scientific Measurements
Precision - Refers to reproducibility or How
close the measurements are to
each other! Accuracy - Refers to how close a
measurement is to the real
value! Systematic error - produces values that
are either all higher
or all lower than the actual value. Random
Error - in the absence of systematic error,
produces some
values that are higher and some that
are lower than the actual value.
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