Chem 106, Prof. J.T. Spencer
1
CHE 106: General Chemistry
CHAPTER
ONE
Copyright © James T. Spencer 1995 - 1999
All Rights Reserved
Chem 106, Prof. J.T. Spencer
2
Matter
 What
is Chemistry
– Study of the “Physical” Properties Matter (Form and Function)
– Study of How Matter Changes (Reactivity)
 Benefits
of Chemistry
– Pharmaceuticals
– Enhanced food production (fertilizers, herbicides, etc...)
– Plastics and Polymers
also: environmental
BIO
economics
 Why Study Chemistry
Medicine electronics
– Core requirement (?)
Physics
agriculture
– Central Science
politics
S.U.
CHEM
etc...
 Employment
B.S.
Engr
GEO
– Many fields
Law
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
3
Chemistry; Common Chemicals
acetic acid .........................................vinegar
calcium hypochloride ......................bleaching powder
calcium sulfate .................................plaster of paris
carbon tetrachloride ....................... cleaning fluid
ferric oxide .......................................iron rust
graphite ............................................ pencil lead
magnesium sulfate ..........................Epsom salts
naphthalene...................................... mothballs
silicon dioxide................................... sand
sodium bicarbonate .........................baking soda
sodium borate................................... borax
sodium hydroxide ............................lye
sulfuric acid...................................... battery acid
sucrose............................................... cane sugar
Chem 106, Prof. J.T. Spencer
Chemistry; Chemical Production
100
H2SO4
1995
Chemical and Engineering News
Billions of lbs
80
N2
60
O2 C2H4
CaO NH3
40
C3H6
H3PO4
NaOH
Cl2
20
0
Sulfuric Nitrogen Oxygen Ethylene
Lime
Ammonia Propylene NaOH Phosphoric Chlorine
4
Chem 106, Prof. J.T. Spencer
5
Nanoscale Chemistry
Use simpler molecular units are molecular-architectural elements
Chem 106, Prof. J.T. Spencer
Nanoscale Chemistry
6
Chem 106, Prof. J.T. Spencer
Nanosystems
7
Chem 106, Prof. J.T. Spencer
8
Nanomachines
Interstellar Space Travel - Significant concepts in
this area include: launch vehicles, the space
elevator, interplanetary transportation, the
swarm concept, smart dust, extraterrestrial
materials utilization, terraforming, suspended
animation, space telescopes and virtual sample
return.
Human Therapeutics - Nanotechnology has
caused scientists to re-examine the problems of
the human body from the perspective of atomicred blood cell
engineering. By assuming a nanotechnological
point of view, the resolution of therapeutic ailments becomes simple.
Nano-Robots and Nano-Computers with advanced Artificial Intelligence Nanotechnology will operate under the control of nano-sized computers
which will manage the process of Molecular Manufacturing. In order to
achieve this, it will be necessary to devise advanced Artificial Intelligence
that will be able to automate and regulate Molecular Manufacturing systems.
Chem 106, Prof. J.T. Spencer
Matter; A Review
 Definition
of Matter
– anything that occupies space and has mass
 States
– gas (vapor); no fixed volume or shape, compressable
– liquid; fixed volume no fixed shape, mostly incompressable
– solid; fixed volume and shape, incompressable
 Forms
– Substances (pure or single); has a fixed composition and distinct
properties. Most things encountered are mixtures of substances.
 Properties
– Physical Properties; can be measured without changing the
substance, i.e., color, density, melting point, etc...
– Chemical Properties; the way a substance changes (reacts), i.e.,
combustion
Chapt. 1.1
9
Chem 106, Prof. J.T. Spencer
10
Matter; A Review
 Changes
– Physical - Changes in appearance but not identity, i.e.,
evaporation, melting (all changes of state)
– Chemical - transformation into a different substance
Chemical Changes
burning
melting
C6H12O6 + 6O2
6CO2 + 6H2O
chemical reactions
NaOH + HCl
H2O + NaCl
corrosion
4Fe + 3O2
Physical Changes
2 Fe2O3
H2O(s)
H2O(l)
sublimation
H2O(s)
H2O(g)
dissolution
H2O(l ) + NaCl(s)
NaCl(aq)
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
11
Matter; A Review
 Mixtures;
combinations of substances
– Mixture- combination of two or more substances in
which each retains its own chemical identity (and
properties). Vary widely by composition (infinite
possibilities of combining ratios), can be separated
using the different physical properties of the
component substances.
– Homogeneous - appears the same throughout
(solutions), liquid, gas and solid solutions are
possible.
– Heterogeneous - mixtures which do not have the
same (uniform) appearance throughout.
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
12
Matter; A Review
 Separating
Mixtures using Physical Properties
– How would you separate;
Salt and Sand Mixture
solubility and filtration
Ink from Cabbage Juice
chromatography
Water from Salt Water
distillation
Iron and Gold Mixture
magnetic properties
melting point differences
chem. reactivity (acids)
Iodine from Copper Chloride
solubility and filtration
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
13
Matter; A Review
 Separating
Mixtures using Physical Properties
– How would you separate;
Filtration
Sand from Salt
Everyday Examples;
Auto Oil Filter
Auto Air Filter
Aquarium Water Filter
Spaghetti Strainer
Window Screens
Registrar
Flow
Filter
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
14
Matter; A Review
 Separating
Mixtures using Physical Properties
– How would you separate;
Distillation
Water from Salt Water
NaCl(s) + H2O(l)
NaCl(aq)
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
15
Matter; A Review
 Separating
Mixtures using Physical Properties
– How would you separate;
Chromatograpgy
Dyes from M&M’s
Before
After
Dyes
Chapt. 1.1
Chem 106, Prof. J.T. Spencer
16
Matter; Elements and Compounds
 Substances
– Elements - substances which cannot be decomposed into simpler
substances (see periodic table)
– Compounds- substances which can be separated into two or more
elements
 Elements
– 110 Known (periodic table to be revisited)
– make up all matter and composed of “subatomic particles”
– symbols used for abbreviations (from older or common names)
 Compounds
– Elements combined in a definite proportion by mass (law of definite
proportion)
– properties different than consititutent elements
Water; example of mixtures, compound and elements?
Chapt. 1.2
Chem 106, Prof. J.T. Spencer
Matter; Elements and Periodic Table
Periodic Table
See Website: http://the-tech.mit.edu/Chemicool
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Chem 106, Prof. J.T. Spencer
18
Matter
Matter
No
Heterogeneous
Mixture
Uniform ?
Yes
Homogeneous
No
Pure Substance
Decomposed ?
No
Element
Yes
Compound
Can be separated
by physical methods
Yes
Homogeneous
Mixture (solution)
Chem 106, Prof. J.T. Spencer
Scientific Method
Form and test
hypothesis
Patterns and
Trends
Theory
Observations
and Experiments
19
Chem 106, Prof. J.T. Spencer
Observations to Theory
Observations
Theory
20
Chem 106, Prof. J.T. Spencer
Observations to Theory
Observations
Theory
21
Chem 106, Prof. J.T. Spencer
Observations to Theory
Observations
Theory
22
Chem 106, Prof. J.T. Spencer
Matter; Measurement
A
B
Which is True?
A=B
A>B
A<B
23
Chem 106, Prof. J.T. Spencer
Matter; Measurement
A
B
Which is True?
A=B
A>B
A<B
24
Chem 106, Prof. J.T. Spencer
Matter; Measurement
A
B
Which is True?
A=B
A>B
A<B
25
Chem 106, Prof. J.T. Spencer
26
Matter; Measurement
 Systems
– Metric - base 10
– SI- international scientific system
– mass
Kilogram
– length
Meter
– time
Second
– electric current
Ampere
– temperature
Kelvin
– light
Candela
– Amount
Mole
 Factor label method for conversions
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
27
Matter; Measurement
 Prefixes
Mega
Kilo
Deci
Centi
Milli
Micro
Nano
M
k
d
c
m

n
106
103
10-1
10-2
10-3
10-6
10-9
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
28
Matter; Measurement
Sample exercise: What fraction of a second is
a picosecond, ps?
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
29
Matter; Measurement
Sample exercise: What fraction of a second is
a picosecond, ps?
10-12 second
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
30
Matter; Measurement
Common Units:
Length and Mass
Length - unit of distance measured in
meters
Mass - measures the amount of matter
in an object in grams
Temperature
Kelvin
Celsius
°C = 5/9 (°F -32)
Chapt. 1.3
K = °C + 273.15
Chem 106, Prof. J.T. Spencer
31
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
32
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
K = °C + 273.15
= -11.5 + 273.15
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
33
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
K = °C + 273.15
= -11.5 + 273.15
= 261.65 K
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
34
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
K = °C + 273.15
= -11.5 + 273.15
= 261.65 K
= 261.7 K
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
35
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
°C = 5/9 (°F -32)
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
36
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
°C = 5/9 (°F - 32)
-11.5 = 5/9(x - 32)
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
37
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
°C = 5/9 (°F - 32)
-11.5 = 5/9(x - 32)
9(-11.5) + 32 = x
5
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
38
Matter; Measurement
Sample exercise: Ethylene glycol, the major
ingredient in antifreeze, freezes at -11.5°C.
What is the freezing point in
a) K
b) °F
°C = 5/9 (°F - 32)
-11.5 = 5/9(x - 32)
9(-11.5) + 32 = x
5
Chapt. 1.3
11.3°F = x
Chem 106, Prof. J.T. Spencer
39
Matter; Measurement
Derived Units:
Volume
Length x length x length
measured in cm3, which is equal to mL
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
40
Matter; Measurement
Derived Units:
Density
amount of mass per unit volume
measured in g/cm3, or g/mL
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
41
Matter; Measurement
Sample exercise: A student needs 15.0 g of
ethanol (ethyl alcohol) for an experiment. If
the density of the alcohol is 0.789 g/mL, how
many milliliters of alcohol are needed?
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
42
Matter; Measurement
Sample exercise: A student needs 15.0 g of
ethanol (ethyl alcohol) for an experiment. If
the density of the alcohol is 0.789 g/mL, how
many milliliters of alcohol are needed?
D = m/V so V = m/D
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
43
Matter; Measurement
Sample exercise: A student needs 15.0 g of
ethanol (ethyl alcohol) for an experiment. If
the density of the alcohol is 0.789 g/mL, how
many milliliters of alcohol are needed?
D = m/V so V = m/D
= 15.0 g
0.789 g/mL
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
44
Matter; Measurement
Sample exercise: A student needs 15.0 g of
ethanol (ethyl alcohol) for an experiment. If
the density of the alcohol is 0.789 g/mL, how
many milliliters of alcohol are needed?
D = m/V so V = m/D
= 15.0 g
0.789 g/mL
= 19.0 mL
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
45
Matter; Uncertainty in Measurement
 Precision
and Accuracy
– Precision - how closely individual measurements
agree
– Accuracy- how closely the measurements agree with
the true value
 Significant
Figures
– All measurements are inaccurate intrinsically
– measured quantities are reported such that the last
figure is uncertain
Chapt. 1.4
Chem 106, Prof. J.T. Spencer
Matter; Uncertainty in Measurement
Good Precision
Good Accuracy
Good Precision
Poor Accuracy
Poor Precision
Poor Accuracy
46
Chem 106, Prof. J.T. Spencer
47
Matter; Uncertainty in Measurement
 Determining
Significant Figures
–all non zero digits are significant
–zeros between nonzero digits are significant
–zeros to the left of first nonzero digit are not
significant
–zeros at the end of a number and to the right of
a decimal point are significant
–when a number ends in a zero but with no
decimal point, the zero may or may not be
signigicant (use scientific notation)
Chapt. 1.4
Chem 106, Prof. J.T. Spencer
48
Matter; Uncertainty in Measurement
 Determining
Significant Figures
3.573 has 4 significant figures
0.073 has 2 significant figures
3.070 has 4 significant figures
0.003 has 1 significant figures
- multiplication and division; result can have no
more than the figure with the fewest significant
figures
- addition and subtraction; result can have the
same number of decimal places as the term with
the least number of decimal places
Chapt. 1.4
Chem 106, Prof. J.T. Spencer
49
Matter; Uncertainty in Measurement
Sample exercise: A balance has a precision of
0.001 g. A sample that weighs about 25 g is
weighed on this balance. How many
significant figures should be reported for this
measurement?
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
50
Matter; Uncertainty in Measurement
Sample exercise: A balance has a precision of
0.001 g. A sample that weighs about 25 g is
weighed on this balance. How many
significant figures should be reported for this
measurement?
25.XXX
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
51
Matter; Uncertainty in Measurement
Sample exercise: A balance has a precision of
0.001 g. A sample that weighs about 25 g is
weighed on this balance. How many
significant figures should be reported for this
measurement?
25.XXX
5 sig figs
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
52
Matter; Uncertainty in Measurement
Sample exercise: How many significant figures
are in each of the following measurements?
A) 3.549 g
B) 2.3 x 104 cm
C) 0.00134 m3
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
53
Matter; Uncertainty in Measurement
Sample exercise: How many significant figures
are in each of the following measurements?
A) 3.549 g
4 sig figs
B) 2.3 x 104 cm
C) 0.00134 m3
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
54
Matter; Uncertainty in Measurement
Sample exercise: How many significant figures
are in each of the following measurements?
A) 3.549 g
4 sig figs
B) 2.3 x 104 cm
2 sig figs
C) 0.00134 m3
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
55
Matter; Uncertainty in Measurement
Sample exercise: How many significant figures
are in each of the following measurements?
A) 3.549 g
4 sig figs
B) 2.3 x 104 cm
2 sig figs
C) 0.00134 m3
3 sig figs
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
56
Matter; Uncertainty in Measurement
Sample exercise: There are exactly 1609.344 m
in a mile. How many meters are in a distance
of 1.35 mi?
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
57
Matter; Uncertainty in Measurement
Sample exercise: There are exactly 1609.344 m
in a mile. How many meters are in a distance
of 1.35 mi?
1.35 mi = 1 mi
x
1609.344 m
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
58
Matter; Uncertainty in Measurement
Sample exercise: There are exactly 1609.344 m
in a mile. How many meters are in a distance
of 1.35 mi?
1.35 mi = 1 mi
x
1609.344 m
x = 2172.6144 m
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
59
Matter; Uncertainty in Measurement
Sample exercise: There are exactly 1609.344 m
in a mile. How many meters are in a distance
of 1.35 mi?
1.35 mi = 1 mi
x
1609.344 m
1.35 has 3 sig figs
1609.344 has 7 sig figs
1 is infinitely significant
x = 2172.6144 m
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
60
Matter; Uncertainty in Measurement
Sample exercise: There are exactly 1609.344 m
in a mile. How many meters are in a distance
of 1.35 mi?
1.35 mi = 1 mi
x
1609.344 m
1.35 has 3 sig figs
1609.344 has 7 sig figs
1 is infinitely significant
x = 2172.6144 m
x = 2170 m
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
61
Dimensional Analysis
 Use
Units throughout the calculation (helps
“guide” calculation.
 Should always yield the proper units
 Uses conversion factors
 Example; How fast is 50 mph in in/sec.?
50 mi.
1 hour
1 hour
3600 sec.
5280 ft
1 mi.
12 in.
1 ft
= in
sec.
Chem 106, Prof. J.T. Spencer
62
Dimensional Analysis
Sample exercise: By using a conversion factor
from the back inside cover, determine the
length in kilometers of a 500.0 mi automobile
race.
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
63
Dimensional Analysis
Sample exercise: By using a conversion factor
from the back inside cover, determine the
length in kilometers of a 500.0 mi automobile
race.
500.0 mi
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
64
Dimensional Analysis
Sample exercise: By using a conversion factor
from the back inside cover, determine the
length in kilometers of a 500.0 mi automobile
race.
500.0 mi 1 km
0.62137 mi
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
65
Dimensional Analysis
Sample exercise: By using a conversion factor
from the back inside cover, determine the
length in kilometers of a 500.0 mi automobile
race.
500.0 mi 1 km
0.62137 mi
= 804.674 km
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
66
Dimensional Analysis
Sample exercise: By using a conversion factor
from the back inside cover, determine the
length in kilometers of a 500.0 mi automobile
race.
500.0 mi 1 km
= 804.674 km
0.62137 mi
* answer can only have 4 sig figs; 804.7 km
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
67
Dimensional Analysis
Sample exercise: The distance between carbon
atoms in a diamond is 154 pm. Convert this
distance to millimeters.
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
68
Dimensional Analysis
Sample exercise: The distance between carbon
atoms in a diamond is 154 pm. Convert this
distance to millimeters.
154 pm
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
69
Dimensional Analysis
Sample exercise: The distance between carbon
atoms in a diamond is 154 pm. Convert this
distance to millimeters.
154 pm
1m
103 mm
1012 pm 1 m
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
70
Dimensional Analysis
Sample exercise: The distance between carbon
atoms in a diamond is 154 pm. Convert this
distance to millimeters.
154 pm
1m
1012 pm
103 mm
1m
= 1.54 x 10-7 mm
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
71
Dimensional Analysis
Sample exercise: A car travels 28 mi to the
gallon of gasoline. How many kilometers per
liter will it go?
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
72
Dimensional Analysis
Sample exercise: A car travels 28 mi to the
gallon of gasoline. How many kilometers per
liter will it go?
28 mi
gal
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
73
Dimensional Analysis
Sample exercise: A car travels 28 mi to the
gallon of gasoline. How many kilometers per
liter will it go?
28 mi
gal
1 km
0.62137 mi
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
74
Dimensional Analysis
Sample exercise: A car travels 28 mi to the
gallon of gasoline. How many kilometers per
liter will it go?
28 mi
gal
1 km
0.62137 mi
1 gal
3.7854 L
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
75
Dimensional Analysis
Sample exercise: A car travels 28 mi to the
gallon of gasoline. How many kilometers per
liter will it go?
28 mi
gal
1 km
0.62137 mi
1 gal
= 11.9041 km
3.7854 L
L
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
76
Dimensional Analysis
Sample exercise: A car travels 28 mi to the
gallon of gasoline. How many kilometers per
liter will it go?
28 mi
gal
1 km
0.62137 mi
* 2 sig figs
1 gal
= 11.9041 km
3.7854 L
L
= 12 km
L
Chapt. 1.3
Chem 106, Prof. J.T. Spencer
77
Chapter One; Review
Matter:
Chemical and Physical Changes
Elements and Compounds
Units of Measurement
Uncertainty and Significant Figures
Precision and Accuracy
“Factor Label” Method (Dimensional
Analysis)