CHEM115
General Chemistry I
Dr. Myton
Class meets MTWR at 11:00 am
CHEM115 General Chemistry I
David M. Myton, Ph.D. (Dr. Myton)
• CRW327 dmyton@lssu.edu
• Pronto: dmyton
• Professor of Chemistry
Introductions
• This class is not a direct competition
• Introduce your self to your neighbor
 Name
 Hometown
 Major
• Class survey
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Biology
Chemistry
Criminalistics
Engineering
Fisheries & Wildlife
Geology
Other
SYLLABUS
• Blackboard – get there through Anchor Access
 Pronto – IM with voice
 Documents, including slide summaries
 writing exercises
• http://edugen.wiley.com – homework,
textbook, video office hours, student solutions
• Supplemental Instruction (SI)
• Bring to class: active chapter of text,
calculator, i-clicker, lecture notes
i-Clicker
• Unique student serial numbers
• Credit given for participation and accuracy
• Bring to EVERY class
A
B
C
D
E
1
2
3
4
5
Yes
No
-
True
False
-
Strongly Agree
Agree
Neutral
Disagree
Strongly Disagree
Essential High School Science
Content: Properties of Matter
C1.1B Evaluate the uncertainties or validity of scientific conclusions
using an understanding of sources of measurement error, the
challenges of controlling variables, accuracy of data analysis, logic of
argument, logic of experimental design, and/or the dependence on
underlying assumptions.
C2.2B Describe the various states of matter in terms of the motion and
arrangement of the molecules (atoms)making up the substance.
C4.2A Name simple binary compounds using their formulae.
C4.2B Given the name, write the formula of simple binary
compounds.
C4.3A Recognize that substances that are solid at room temperature
have stronger attractive forces than liquids at room temperature, which
have stronger attractive forces than gases at room temperature.
C4.3B Recognize that solids have a more ordered, regular arrangement
of their particles than liquids and that liquids are more ordered than
gases.
Essential High School Science
Content: Properties of Matter
C4.8A Identify the location, relative mass, and charge for electrons,
protons, and neutrons.
C4.8B Describe the atom as mostly empty space with an extremely
small, dense nucleus consisting of the protons
and neutrons and an electron cloud surrounding the nucleus.
C4.8C Recognize that protons repel each other and that a strong force
needs to be present to keep the nucleus
intact.
C4.8D Give the number of electrons and protons present if the fluoride
ion has a -1 charge.
C4.9A Identify elements with similar chemical and physical properties
using the periodic table.
C4.10A List the number of protons, neutrons, and electrons for any
given ion or isotope.
C4.10B Recognize that an element always contains the same number
of protons.
Essential High School Science
Content: Properties of Matter
C5.2A Balance simple chemical equations applying the
conservation of matter.
C5.2B Distinguish between chemical and physical changes
in terms of the properties of the reactants and products.
C5.2C Draw pictures to distinguish the relationships
between atoms in physical and chemical changes.
C5.4A Compare the energy required to raise the
temperature of one gram of aluminum and one gram of
water
the same number of degrees.
C5.5A Predict if the bonding between two atoms of
different elements will be primarily ionic or covalent.
C5.4B Predict the formula for binary compounds of main
group elements.
Chemistry & Environmental
Sciences Student Organization
1st Meeting: Wednesday September 2 at
NOON in Crawford Hall Upstairs Lobby
(w/ pizza)
1st Function: Camping at Muskellunge Lake
Leaving Soo Saturday Sept 5 at NOON,
returning Monday Sept 7 mid-day.
Campsites and dinner provided by club
Chapter 1: Fundamental Concepts and Units
of Measurement:
Learning Objectives
• Upon completion of the chapter, the student should:
• Know how chemistry fits into the sciences and everyday life.
• Understand the difference between chemical reactions and
physical changes.
• Understand the Law of Conservation of Energy.
• Be able to convert between ºF, ºC and K.
• Know the difference between precision and accuracy.
• Have a basic understanding of significant figures.
• Know the basic SI units.
• Be able to convert between calories and joules.
• Be able to determine the density, mass, or volume of a
substance when given two of these three variables.
Cumulative
• accumulative: increasing by successive
addition; "the benefits are cumulative"; "the
eventual accumulative effect of these
substances"
wordnet.princeton.edu/perl/webwn
• Incorporating all data up to the present
en.wiktionary.org/wiki/cumulative
“Parfaits are delicious” - donkey
Juggling?
"Scientific knowledge is a body of statements
of varying degrees of certainty -- some most
unsure, some nearly sure, but none absolutely
certain ... Now, we scientists are used to this,
and we take it for granted that it is perfectly
consistent to be unsure, that it is possible to
live and not know."
Richard Feynman (1918-1988)
Nobel Prize in Physics, 1965
Chapter 1:Fundamental Concepts
and Units of Measurement
Brady & Senese 5th Ed
15
A Chemist’s View
01m11vd1.mov
Macroscopic
Symbolic
2 H2(g) + O2 (g)  2 H2O(g)
Particulate (Molecular)
Chemistry and the Sciences
• Chemistry- the study of the composition of
matter and its transformations
• Matter- anything that takes up space and
has mass
• Chemical reaction- change that results from
the interaction of matter.
1.1. Chemistry is important for anyone studying the sciences
17
Scientific Method : Getting Started
Observe a Phenomenon-accurately
describe something we see, taste, feel,
smell or hear
Pose A Question
To Explain The Phenomenon
Form a Hypothesis-a
tentative explanation of the
phenomenon
1.2. The scientific method helps us build models of nature
18
Scientific Method: Testing the Hypothesis
Experiment to Prove or Disprove
Hypothesis
If experiment proves
hypothesis,
form theory (theoretical model)
If experiment disproves
hypothesis,
Pose new question or hypothesis
Continue experimentation.
If results form pattern, considered
a law
1.2. The scientific method helps us build models of nature
19
It is the mark of an educated mind
to be able to entertain a thought
without accepting it.
Aristotle (384 BC - 322 BC)
Question:
Which statement is a hypothesis?
a: Objects on Earth are attracted by
gravity.
b: When pushed off the table, my chemistry
book will fall to the floor.
c: Opposite charges repel each other.
d: Mass can be converted into energy.
Scientific Method Case Study:
The Process of Growth
• A child sees that a seed, when planted in soil, watered,
and exposed to sunlight, grows to form a flower. He
concludes that all living things require sunlight, water,
and burial in soil to grow.
• Build a case for rebuttal using the scientific method.
1.2. The scientific method helps us build models of nature
22
Your Turn!
Which of the following is not a hypothesis
for the observed plant growth?
A.
B.
C.
D.
soil is necessary to all growth
light is essential to growth of the seed
water is required to allow growth
plants grow to a greater height if they
receive fertilizer
E. none of the above
1.2. The scientific method helps us build models of nature
23
Your Turn!
A chicken egg is buried, left in the sun, and watered.
A second egg is left above the soil, watered and
left in the sun. Would this prove that soil is
necessary to growth?
A. Yes
B. No
1.2. The scientific method helps us build models of nature
24
The Scientific Method- Evaluating The Data
A theory is an explanation (based on well-tested,
internally consistent experimental results)
about why the phenomenon may occur




it should explain currently available data
It should be as simple as possible
It should clearly show underlying connections
It should accurately predict future behaviors
1.2. The scientific method helps us build models of nature
25
The Scientific Method is Cyclical
1.2. The scientific method helps us build models of nature
26
Question:
Which describes a tested explanation of
behavior of nature?
a: a scientific law
b: a theory
c: a hypothesis
d: empirical facts
Atomic Theory Helps Us Visualize Matter
• Air inflates a balloon
 air must be composed of matter
 the matter is colliding with the walls
of the container.
• A leaf floats on water’s surface
 water is composed of particles that
occupy space
• A leaf falls through air, but rests
on water’s surface
 particles are closer in liquid than in
gases
1.2. The scientific method helps us build models of nature
28
Models Helps Us
Visualize Matter
1.2. The scientific method helps us build models of nature
29
Changes in Matter
• Chemical change- a process that results in the
formation of a new substance
• Evidence? Formation of a new solid, new liquid,
new gas, temperature change, or an unexpected
color change
• Physical change- a process that results in no new
substance, but that may change the state of those
present, or the proportions
1.3. Matter is Composed of Elements, Compounds, and Mixtures
31
Question:
What properties change when a substance
undergoes a chemical reaction?
a: physical properties
b: chemical properties
c: both chemical and physical properties
d: neither chemical nor physical properties
Learning Check: Chemical Or Physical Change?
Chemical
Physical
Magnesium burns when heated
in a flame
Magnesium metal tarnishes in
air
Magnesium metal melts at
922K
Grape Kool-aid lightens when
water is added
1.3. Matter is Composed of Elements, Compounds, and Mixtures
33
Your Turn!
Which of the following is not a chemical change?
A.
B.
C.
D.
E.
a match burns in air
ice melts in air
an aluminum door whitens in air
all of these
none of these
1.3. Matter is Composed of Elements, Compounds, and Mixtures
34
• Matter can be classified (figure 1.10 p12):
(Molecule or
Formula unit)
(Atom)
Elements are substances that
cannot be decomposed by
chemical means into simpler
substances
chemical symbol
 Most are one or two letters
 First letter is always capitalized
 All remaining letters are
lowercase
 Names and chemical symbols of
the elements are listed on the
inside front cover of the book
Elements
• Learn the name,
spelling and
symbol for
elements #1-30,
Au, Ag, Hg, Pb,
Br, I
Name
Symbol
Sodium
Copper
Cl
Nitrogen
K
Atomic naming
Sb
antimony stibium
K
potassium kalium
Cu
copper
cuprum
Sn tin
stannum
Au
Gold
aurum
Na sodium
natrium
Ag
silver
argentum
W tungsten
wolfram
Fe
iron
ferrum
Hg mercury
hydragyrum
Pb
lead
plumbum
1.3. Matter is Composed of Elements, Compounds, and Mixtures
38
What Is A Compound?
• Compounds - formed from two or more atoms of
different elements combined in a fixed
proportion
• Have different characteristics than the elements
that compose them
• Can be broken down into elements by some
chemical changes
1.3. Matter is Composed of Elements, Compounds, and Mixtures
39
A MOLECULE is the smallest
unit of a compound that retains the
chemical characteristics of the
compound.
MOLECULAR FORMULA
C8H10N4O2 - caffeine
H2O
Mixtures
• mixtures consist of varying
amounts of two or more
elements or compounds
• Homogeneous mixtures or
“solutions”- have the same
properties throughout the
sample
 Brass, tap water
• Heterogeneous mixturesconsist of two or more phases
 Salad dressing, Coca-Cola ™
1.3. Matter is Composed of Elements, Compounds, and Mixtures
41
Learning Check: Classification
Sand Ice
Flour
(H2O)
Table
Salt
(NaCl)
Pure
Element
Compound
Molecule
Heterogeneous Mix
Homogeneous Mix
1.3. Matter is Composed of Elements, Compounds, and Mixtures
43
Classification Of Matter By State
Classification by state is based on packing, motion,
and shape
 Solids have fixed shape and volume
 Liquids have fixed volume, but take the container shape
 Gases have to expand to fill the shape and volume of
the container
44
Properties Of Matter
• Chemical properties describe the behavior
of the matter that leads to the formation of a
new substance: the "reactivity" of the
substance
• Physical properties can be observed about
the matter alone, without changing the
composition
1.4. Properties of matter can be classified in different ways
45
Learning Check: Chemical or Physical
Property?
Chemical Physical
Magnesium metal is grey
Magnesium metal tarnishes in
air
Magnesium metal melts at
922K
Magnesium reacts violently
with hydrochloric acid
1.4. Properties of matter can be classified in different ways
46
Your Turn!
Which of the following is a chemical
property?
A. water is colorless
B. water reacts violently with solid Na metal
C. water dissolves table salt
D. all of these
E. none of these
1.4. Properties of matter can be classified in different ways
47
Question:
Intensive properties are Independent of
the quantity of material present
Which is an extensive physical property?
a: mass
b: melting point
c: reactivity with water
d: temperature
Measurements are Observations
• Qualitative observations are non-numerical•
•
- ask “what” or “how” or “why”
Quantitative observations are numerical-ask “how much” and are also called
measurements
This course is general chemistry with
quantitative analysis
1.5 Measurements are essential to describe properties
49
Your turn!
Which of the following is a quantitative
observation?
A. the height of the plant
B. the mass of water added
C. the temperature of the day
D. all of the above
E. none of the above
1.5 Measurements are essential to describe properties
50
Measurement
Measurements:
• Always involve a comparison
• Require units
• Involve numbers that are inexact (estimated).
•
This uncertainty is due to the limitations of
the observer and the instruments used
In science, all digits in a measurement up to
and including the first estimated digit are
recorded
1.5 Measurements are essential to describe properties
52
Which types of numbers are considered “exact?” Below are the general rules.
1. Conversions between units within the English System are exact.
e.g. 12 in = 1 ft or 12 in/1 ft
(In this conversion, 12 and 1 are both exact.)
2. Conversions between units within the Metric System are exact.
e.g. 1 m = 100 cm or 1 m/100 cm
(In this conversion, 1 and 100 are both exact.)
3. Conversions between English and Metric system are generally NOT exact.
Exceptions will be pointed out to you.
e.g. 1 in = 2.54 cm exactly
(1 and 2.54 are both exact.)
e.g. 454 g = 1 lb or 454 g/1 lb
(454 has 3 sig. fig., but 1 is exact.)
4. “Per” means out of exactly one.
e.g. 45 miles per hour means 45 mi = 1 hr or 45 mi/1 hr.
exactly one.)
5. “Percent” means out of exactly one hundred.
e.g. 25.9% means 25.9 out of exactly 100 or 25.9/100
exact.)
(45 has 2 sig. fig. but 1 is
(25.9 has 3 sig. fig., but 100 is
6. Counting numbers are exact. Sometimes it is hard to decide whether a number is a
“counting number” or not. In most cases it would be obvious. Ask when in doubt.
e.g.There are 5 students in the room. (5 would be an exact number because you cannot have
a fraction of a student in the room.)
Measurements and units
• In the U.S., we use the Imperial (USCS) System
•
•
•
(United States Customary System units)
The scientific community (and most of the world)
uses the metric system
Variations in the metric system exist, thus a
standard system is used: International System of
Units (SI)
SI units we will use now:
 Length (m) Mass (kg) Time (s) Temperature (K)
1.5 Measurements are essential to describe properties
54
Mass- Matter Content
USCS: oz (avdp.), lb, T
Metric: g
SI: kg
1.5 Measurements are essential to describe properties
55
Length
USCS: in, ft, yd, mi
Metric: L, cm3
SI: m
1.5 Measurements are essential to describe properties
56
Volume-bulk
• measured directly, using
•
•
•
•
equipment for
volumetric measure
calculated using
dimensional (length)
information and
appropriate formulas.
1 cm3= 1mL
USCS: fl. oz., pt., qt.,
gal
Metric: L, cm3
SI: m3
1.5 Measurements are essential to describe properties
57
Temperature
• USCS: °F
• Metric: °C
• SI: K
1.5 Measurements are essential to describe properties
58

9 F


tF    tC  32 F
5 C
1K 

TK  tC  273.15 C  
1 C 

Your Turn!
Which of the following is the lowest
temperature?
A. 300. K
B. 16 ºC
C. 55 ºF
D. they are the same
1.5 Measurements are essential to describe properties
60
Question
Measurement Error
•
•
•
•
Because each measurement involves an estimate,
measurements always have error.
Record all measured numbers, including the first
estimated digit
These digits are called significant digits or
significant figures
Exact numbers have infinite significant digits
1.6. Measurements always contain some uncertainty
62
Significant Digits In A Measurement Are
Limited By Instrument Precision
• Using the first thermometer, the
temperature is 21.3 ºC (3
significant digits)
• Using the more precise (second)
thermometer, the temperature is
21.32 ºC (4 significant digits)
1.6. Measurements always contain some uncertainty
63
Measurement Exercise
• Complete the following
table
• Convert the area in mm2
to in2 and from in2 to mm2
and record.
• Note that 2.54 cm = 1 in
mm
Length
Width
Area
Converted
area:
in
Errors Arise From A Number Of Sources
Including:
• Errors-inherent error due to the equipment or
procedure
 Changing volume due to thermal expansion or contraction
(temperature changes)
 Improperly calibrated equipment
 procedural design allows variable measurements
• Mistakes-blunders that you know that you have made.
Do not use these data




Spillage
Incomplete procedures
Reading scales incorrectly
Using the measuring device incorrectly
1.6. Measurements always contain some uncertainty
65
Reducing Error:
• Errors can often be detected by making repeated
•
•
measurements
Error can be reduced by calibrating equipment
The average or mean reduces data variations: it
helps find a central value
1.6. Measurements always contain some uncertainty
66
Accuracy vs. Precision
• An accurate measurement is close to the true or
•
•
correct value, a “hole-in-one”
A precise measurement is close to the average of a
series of repeated measurements
When calibrated instruments are used properly, the
greater the number of significant figures, the greater
is the degree of precision for a given measurement
1.6. Measurements always contain some uncertainty
67
Question
Measurements with lots of scatter are probably
considered:
a: not accurate and not precise.
b: not accurate, but precise.
c: not precise, but accurate.
d: precise and accurate.
Question
Nonzero digits in a measured number are
always significant
Zeros must be considered more carefully:
 Zeros between significant digits are
significant
 Zeros to the right of the decimal point are
always counted as significant
 Zeros to the left of the first nonzero digit are
never counted as significant
 Zeros at the end of a number without a
decimal point are assumed not to be
significant
How many significant figures?
200.0
12100
21000
1010
200.001
0.98700
0.000012
2.200002
125
1.25e2
1.250e-3
125000
0.00125
6.2303e23
6 230 300 000 000
• Measurements limit the precision of the results
calculated from them
• Rules for combining measurements depend on the
type of operation performed:
 Multiplication and division
The number of significant figures in the answer
should not be greater than the number of significant
figures in the least precise measurement.
3.14  2.751
0.64
 13
(3 sig.figs.)  (4 sig.figs.)
(2 sig.figs.)
 (2 sig. figs.)
 Addition and Subtraction
The answer should have the same number of
decimal places as the quantity with the
fewest number of decimal places
3.247
41.36
+125.2
169.8
 3 decimal places
 2 decimal places
 1 decimal place
 answer rounded to 1 decimal place
Note: Remember that some numbers are exact. Numbers that come
from definitions or direct counts have no uncertainty and can be
assumed to contain an infinite number of significant figures.
Question
Question
Question
What is the proper way to report the sum 1.150 m +
3.3 m?
a: 4.45 m
b: 4.4 m
c: 4.5 m
d: 4.450 m
Dimensional Analysis
• We plan to bike the 14.1 miles from the university
to Brimley State Park What is the distance in km
given that 0.6215 mi = 1 km?
• What is the distance in meters?
Dimensional Analysis
• We plan to bike the 14.1 miles from the university
to Brimley State Park If we travel at a rate of 17
miles per hour how many minutes will the trip
take?
Dimensional Analysis
• If we drive the 14.1 miles from the university to
Brimley State Park and get 22.4 mpg in our car,
what will the cost of the trip be if gas is $2.56/gal?
USCS Unit Conversions
Mass
Volume
16 oz. (avdp.) = 1 lb. 3 tsp. = 1 Tbsp.
2000 lb. = 1 T.
16 Tbsp. = 1 c.
2 c. = 1 pt.
2 pt. = 1 qt.
4 qt. = 1 gal.
8 fl. oz. = 1 c.
1.7 Units can be converted using the factor-label method
Distance
12 in. = 1 ft.
3 ft. = 1 yd.
1760 yd. = 1 mi.
81
USCS And Metric Units Are Related Using “Critical
Links”
Length
Mass
Volume
USCS to Metric Metric to USCS
1 in. = 2.54 cm
1 m = 39.37 in
1 yd = 0.9144 m 1 km = 0.6215 mi
1 mi = 1.609 km
1 lb = 453.6 g
1 kg = 2.205 lb
1 oz = 28.35 g
1 gal = 3.785 L
1 L = 1.0567 qt
1 qt = 946.4 mL
1 oz (fluid) = 29.6 mL
It is also useful to know that 1 mL = 1 cm3=1 cc
1.7 Units can be converted using the factor-label method
82
Building Conversion Factors in Unit
Conversions
1. Write the number to be converted as a fraction
(with units)
2. Identify the target units
3. Are the starting units in the same system as the
target?
 If not, you will need a critical link.
 USCS→USCS Conversions: Write down the
conversion factors from smallest to largest .
 metric →metric conversions: Write down the
definitions of all prefixed units.
1.7 Units can be converted using the factor-label method
83
Building Conversion factors (cont).
4. Use the form of the conversion factor that allows
the units to cancel--they must be on opposite
levels of the fraction to cancel.
5. Continue adding conversion factors until the
units match the target units.
2nd Check- are all units written on the page two
times? If so, you have enough info to start the
problem.
1.7 Units can be converted using the factor-label method
84
Question
What conversion factors would be necessary to convert
miles per gallon to km per liter?
a: (1.6 km / 1 mi) and (1 gal / 3.79 L)
b: (1 mi / 1.6 km) and (1 gal / 3.79 L)
c: (1.6 km / 1 mi) and (3.79 L / 1 gal)
d: (1 mi / 1.6 km) and (3.79 L / 1 gal)
Question
What is the volume of a box that measures 50 cm by 1.0
m by 2000 mm?
a: 100,000 m3
b: 10,000 m3
c: 100 m3
d: 1.0 m3
e: 1 m3
If there are exactly 2.54 cm in one inch ,
what is the volume of a cube 1 foot on each
side in units of cubic centimeters?
Chalcopyrite, the principle ore of copper (Cu)
contains 34.63 percent Cu by mass. How
many grams of Cu can be obtained from
5.11e3 kg of the ore?
If a bracelet is made of silver and copper with a
mass of 38.9 g contains 32.3 g of silver, what is
the percentage of silver and of copper. How
many grams of copper are in a 50 gram bracelet?
Density (d) is an intensive property defined as the ratio
of an objects mass (m) to volume (v), d
Density(g/cm3)
Water
1.00
Aluminum 2.70
Iron
7.86
Gold
19.3
Air
0.0012
•characteristic of pure substances
at a specified temperature
•Since most substances expand
when heated, densities decrease
when heated.
•units : g/L for gases and g/mL for
solids and liquids.
= m/v
Problem Solving
• The density of ethanol, a colorless liquid that is commonly
known as grain alcohol, is 0.798 g/mL. Calculate the
mass of 17.4 mL of the liquid
• Calculate the volume of 17.4 g of the liquid
A student pipets 25.0 0mL of isopropyl alcohol
into an empty flask weighing 35.182 g. She
finds the mass of the flask + alcohol is
54.707 g. Calculate the density of the
alcohol.
The density of a solution of sulfuric acid is 1.285
g/cm3, and it is 38.08% acid by mass. What volume
of the acid solution in mL do you need to supply
125 g of sulfuric acid?
A solution of sugar in water has a density of 1.05
g/cm3. If you have 250. mL of the solution and
if the solution is 8.1% by weight sugar, how
many grams of sugar are in the solution.
Question
Air at room temperature has a density of about 0.0012
g/cm3. What is the mass of 1.0 L of air?
a: 1.2 g
b: 12 g
c: 0.0012 g
d: none of these
Learning Check:
A crash sounds from the lab- a large vial of mercury
has fallen from a broken shelf. We call the
hazardous materials team to report the spill, about
2.0 quarts of mercury. They ask for the mass- what
is it? (hint: d=13.69g/mL & 1 L = 1.0567 qt)
1.8. Density is a useful intensive property
96
Amethyst is a colored form of the mineral quartz in which
the purple color comes from traces of the element
manganese. To determine the density of amethyst,
you take a stone having a mass of 15.25 g and place it
in a 100. mL graduated cylinder containing 45.0 mL of
water. On adding the stone the water surface rises to
the 50.8 mL mark. What is the density of amethyst?