Chemistry is the study of matter and the transformations it can
undergo
Slide 3
Matter is anything that occupies space.
Slide 4
The Six Levels of Thought Knowledge Comprehension Application
Analysis Synthesis Evaluation Success is a journey, not a
destination. -Ben Sweetland Successful students make mistakes, but
they dont quit. They learn from them. -Ralph Burns Success consist
of a series of little daily efforts. -Marie McCuillough
Slide 5
Basic Safety Rules Use common sense. No unauthorized
experiments. No horseplay. Handle chemicals/glassware with
respect.
Slide 6
Safety Features of the Lab safety shower fire blanket fire
extinguisher eye wash fume hood circuit breaker switch
Slide 7
Government Regulation The government regulates chemicals to
protect the OSHA worker FDA USDA FAA CPSC consumer EPA
environment
Slide 8
Chemical Exposure a one-time exposure causes damage acute
exposurechronic exposure damage occurs after repeated exposure
Slide 9
Toxicity Which is more toxic? Chemical A: LD 50 = 3.2 mg/kg
Chemical B: LD 50 = 48 mg/kg Chemical A is more toxic because less
of it proves fatal to half of a given population.
Slide 10
The Functions of Science pure scienceapplied science the search
for knowledge; facts using knowledge in a practical way
Slide 11
Pure Science The search for facts about the natural world. ? -
In science, we often try to establish a cause-effect relationship.
- Driven by curiosity: the need to know, explore, conquer something
new.
Slide 12
Fundamental Properties of Models A model does not equal
reality. Models are oversimplifications, and are therefore often
wrong. Models become more complicated as they age. We must
understand the underlying assumptions in a model so that we dont
misuse it.
Slide 13
Using the scientific method requires that one be a good
observer. observationinference involves a judgment or assumption
uses the five senses
Slide 14
Data Observations are also called data. There are two types of
data. qualitative dataquantitative data descriptions; measurements;
no numbersmust have numbers and UNITS
Slide 15
Parts of the Scientific Method Identify an unknown. Make a
hypothesishypothesis (a testable prediction). Experiment to
testExperiment the hypothesis. Draw a valid conclusion.
Slide 16
Hypotheses A tentative explanation for the observations May not
be correct, but it puts the scientists understanding of the system
being studied into a form that can be tested Copyright 2007 Pearson
Benjamin Cummings. All rights reserved.
Slide 17
Experiments Tests the validity of the hypothesis Are systematic
observations or measurements made under controlled conditions, in
which the variable of interest is clearly distinguished from any
others If experimental results are reproducible, they are
summarized in a law. Copyright 2007 Pearson Benjamin Cummings. All
rights reserved.
Slide 18
A Scientific Experiment procedure the order of events in an
experiment; the recipe Experiments must be controlled; they must
have two set-ups that must differ by only one variable. The
conclusion must be based on the data. variable any factor that
could influence the result
Slide 19
Scientific Method Observations Hypothesis Experimentation
Controlled (one variable changed at a time) Collect data
(quantitative and qualitative) Analyze data (graph,
statisticstrends) Form valid conclusion. After many experimentsform
a theory.
Slide 20
Fundamental Properties of Models A model does not equal
reality. Models are oversimplifications, and are therefore often
wrong. Models become more complicated as they age. We must
understand the underlying assumptions in a model so that we dont
misuse it.
Slide 21
Scientific Law vs. Scientific Theory Law of Gravity A theory
tries to explain why or how something happens. A law states what
happens. Theory of Gravity Atomic Theory Collision Theory of
Reactions
Slide 22
Experiments Law A verbal or mathematical description of a
phenomenon that allows for general predictions Describes what
happens and not why Unlikely to change greatly over time unless a
major experimental error is discovered Theory Attempts to explain
why nature behaves as it does Is incomplete and imperfect, evolving
with time to explain new facts as they are discovered Copyright
2007 Pearson Benjamin Cummings. All rights reserved.
Slide 23
Make observation Ask question Develop hypothesis Develop
hypothesis Test hypothesis with an experiment Test hypothesis with
an experiment Analyze data and draw conclusions Analyze data and
draw conclusions Hypothesis IS supported Hypothesis IS supported
Hypothesis is NOT supported Hypothesis is NOT supported Develop
theory Develop theory Test hypothesis with further experiments Test
hypothesis with further experiments Revise hypothesis Revise
hypothesis Wysession, Frank, Yancopoulos, Physical Science Concepts
in Action, 2004, page 8 Scientific Method
Slide 24
Then And Question Research Hypothesis Procedure/ Method
Procedure/ Method Data Observations Conclusion What does the
scientist want to learn more about? What does the scientist want to
learn more about? Gathering of information An Educated guess of an
answer to the question An Educated guess of an answer to the
question Written and carefully followed step-by-step experiment
designed to test the hypothesis Written and carefully followed
step-by-step experiment designed to test the hypothesis Information
collected during the experiment Information collected during the
experiment Written description of what was noticed during the
experiment Written description of what was noticed during the
experiment Was the hypothesis correct or incorrect? Was the
hypothesis correct or incorrect? Next Then Next And Finally First
Scientific Method An Overview
Slide 25
Phlogiston Theory (a) When an object burns it gives off a
substance called phlogiston. (b) When the space surrounding the
burning object is filled with phlogiston, the object will no longer
be able to burn. Phlogiston theory of burning Dorin, Demmin, Gabel,
Chemistry The Study of Matter, 3 rd Edition, 1990, page 4
phlogiston (a) (b)
Slide 26
Combustion Theory Modern theory of burning (c) When an object
burns, it uses up a substance (oxygen) in the surrounding space.
(d)When the space surrounding the burning object has too little
oxygen in it, the object will no longer be able to burn. Antoine
Lavoiser Dorin, Demmin, Gabel, Chemistry The Study of Matter, 3 rd
Edition, 1990, page 4 oxygen (c) (d)
Slide 27
Phlogiston Theory of Burning 1. Flammable materials contain
phlogiston. 2. During burning, phlogiston is released into the air.
3. Burning stops when object is out of phlogiston, or the
surrounding air contains too much phlogiston.
Slide 28
Laboratory Equipment
Slide 29
Copper was used to make bullet shells in WW II. By 1943, the
supply of copper metal was in short supply. The US government did
not want to waste copper on making pennies. Pennies were made with
steel metal. They looked silver. Zinc Pennies Before 1982, all
pennies were solid copper (except 1943). After 1982, pennies were
made from zinc. A thin coating of copper was pressed on the zinc. A
shortage of copper drove the price of copper up in the early 1980s.
If melted down, the copper could be sold for more than one
cent.
Slide 30
transmutation In ordinary chemical reactions, we cannot
transmute elements into different elements. changing one substance
into another COPPER GOLD Philosophers Stone
Slide 31
Areas of Chemistry organic physical inorganic biochemistry
everything except carbon e.g., compounds containing metals the
study of carbon- containing compounds measuring physical properties
of substances e.g., the melting point of gold the chemistry of
living things
Slide 32
EPA environment consumer worker OSHA Consumer Product Safety
Commission, USDA, BATF, FDA Government Regulation of Chemicals to
protect the
Slide 33
Measurements Numbers science is based on measurements all
measurements have: - magnitude - uncertainty - units mathematics is
based on numbers exact numbers are obtained by: - counting -
definition
Slide 34
Graphs Line Graph Used to show trends or continuous change Bar
Graph Used to display information collected by counting Pie Graph
Used to show how some fixed quantity is broken down into parts
Slide 35
Convert 41.2 cm 2 to m 2. 100 cm 1 m () ______ X m 2 = 41.2 cm
2 X m 2 = 41.2 cm. cm Recall that41.2 cm 2 = 41.2 cm. cm 100 cm 1 m
() ______ X m 2 = 41.2 cm 2 =0.412 m 2 =0.412 cm. m WRONG! ()
______ 100 cm 1 m =0.00412 m 2 () ______ 100 cm 1 m 2 =0.00412 m
2
Slide 36
Convert 41.2 cm 2 to mm 2. X mm 2 = 41.2 cm 2 X mm 2 = 41.2 cm.
cm Recall that41.2 cm 2 = 41.2 cm. cm 1 cm 10 mm () _____ =4,120 mm
2 = 1 cm 10 mm () _____ 4,120 mm 2 1 cm 10 mm 2 () _____
Slide 37
Measured dimensions of a rectangular solid: Find volume of
solid. L W H Length = 15.2 cm Width = 3.7 cm Height = 8.6 cm V = L.
W. H = (15.2 cm)(3.7 cm)(8.6 cm) =480cm 3
Slide 38
Convert to m 3. X m 3 = 480 cm 3 =0.000480 m 3 100 cm 1 m 3 ()
_____ X m 3 = 480 cm 3 = X m 3 = 480 100 cm 1 m () _____ 100 cm 1 m
() _____ 100 cm 1 m () _____ = or cm. cm. cm 1 m 1000000 cm ( )
_________ 3 3 4.80 x 10 -4 m 3 or 3 2 cm
Slide 39
Measured dimensions of a rectangular solid: Find volume of
solid. L W H Length = 15.2 cm Width = 3.7 cm Height = 8.6 cm V = L.
W. H = (0.152 m)(0.037 m)(0.086 m) =0.000480 m 3 0.152 m 0.037 m
0.086 m Convert to m 3...
Slide 40
Convert to mm 3.
Slide 41
= -6.525 x 10 -9 = 5.3505 x 10 3 or 5350.5 = 5.84178499 x 10
-13 report -6.5 x 10 -9 (2 sig. figs.) report 5.35 x 10 3 (3 sig.
figs.) report 5.84 x 10 -13 (3 sig. figs.) = 2.904 x 10 23 report
2.9 x 10 23 (2 sig. figs.) = -3.07122 x 10 16 report -3.1 x 10 16
(2 sig. figs.)
Slide 42
Rule for Multiplication Calculating with Numbers Written in
Scientific Notation When multiplying numbers in scientific
notation, multiply the first factors and add the exponents. Sample
Problem: Multiply 3.2 x 10 -7 by 2.1 x 10 5 (3.2) x (2.1) = 6.72
(-7) + (5) = -2 or 10 -2 6.72 x 10 -2 Exercise: Multiply 14.6 x 10
7 by 1.5 x 10 4 2.19 x 10 12
Slide 43
Rule for Division Calculating with Numbers Written in
Scientific Notation When dividing numbers in scientific notation,
divide the first factor in the numerator by the first factor in the
denominator. Then subtract the exponent in the denominator from the
exponent in the numerator. Sample Problem: Divide 6.4 x 10 6 by 1.7
x 10 2 (6.4) (1.7) = 3.76 (6) - (2) = 4 or 10 4 3.76 x 10 4
Exercise: Divide 2.4 x 10 -7 by 3.1 x 10 14 7.74 x 10 -22..
Slide 44
Rule for Addition and Subtraction Calculating with Numbers
Written in Scientific Notation In order to add or subtract numbers
written in scientific notation, you must express them with the same
power of 10. Sample Problem: Add 5.8 x 10 3 and 2.16 x 10 4 (5.8 x
10 3 ) + (21.6 x 10 3 ) =27.4 x 10 3 Exercise: Add 8.32 x 10 -7 and
1.2 x 10 -5 1.28 x 10 -5 2.74 x 10 4
Slide 45
Using Scientific Notation for Expressing the Correct Number of
Significant Figures Measurement Number of significant figures it
contains Measurement Number of significant figures it contains 25 g
0.030 kg 1.240560 x 10 6 mg 6 x 10 4 sec 246.31 g 20.06 cm 1.050 m
0.12 kg 1240560. cm 6000000 kg 6.00 x 10 6 kg 409 cm 29.200 cm
0.02500 g 2 2 7 1 5 4 4 2 7 1 3 3 5 4
Slide 46
chemical reaction a rearrangement of atoms such that what you
end up withproducts differs from what you started
withreactants
Slide 47
methane + oxygen + H 2 O(g) carbon dioxide O 2 (g)CO 2 (g)CH 4
(g)+ water+ 22 Combustion of a Hydrocarbon
Synthesis taking small molecules and putting them together,
usually in many steps, to make something more complex
Photosynthesis Sunlight Carbon Dioxide Water Oxygen Glucose CO 2 +
H 2 O O 2 + C 6 H 12 O 6
Slide 50
The International System of Units Lengthmeter m Masskilogram kg
Timesecond s Amount of substancemole mol Thermodynamic
temperatureKelvin K Electric currentamperes amps Luminous
intensitycandela cd QuantityNameSymbol Dorin, Demmin, Gabel,
Chemistry The Study of Matter, 3 rd Edition, 1990, page 16
Slide 51
Derived Units Commonly Used in Chemistry Areasquare meter m 2
Volumecubic meter m 3 Forcenewton N Pressurepascal Pa Energyjoule J
Powerwatt W Voltagevolt V Frequencyhertz Hz Electric chargecoulomb
C Quantity Name Symbol
Slide 52
Area and Volume: Derived Units Area = length x width = 5.0 m x
3.0 m = 15 ( m x m) = 15 m 2 Volume = length x width x height = 5.0
m x 3.0 m x 4.0 m = 60 ( m x m x m) = 60 m 3
Slide 53
Prefixes in the SI System Power of 10 for Prefix SymbolMeaning
Scientific Notation
_______________________________________________________________________
mega-M 1,000,00010 6 kilo-k 1,00010 3 deci-d 0.110 -1 centi-c
0.0110 -2 milli-m 0.00110 -3 micro- 0.00000110 -6 nano-n
0.00000000110 -9 The Commonly Used Prefixes in the SI System
Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 118
Slide 54
Quantities of Mass Kelter, Carr, Scott, Chemistry A Wolrd of
Choices 1999, page 25 Earths atmosphere to 2500 km Ocean liner
Indian elephant Average human 1.0 liter of water Grain of table
salt Typical protein Uranium atom Water molecule 10 24 g 10 21 g 10
18 g 10 15 g 10 12 g 10 9 g 10 6 g 10 3 g 10 0 g 10 -3 g 10 -6 g 10
-9 g 10 -12 g 10 -15 g 10 -18 g 10 -21 g 10 -24 g Giga- Mega- Kilo-
base milli- micro- nano- pico- femto- atomo-
Slide 55
SI-US Conversion Factors RelationshipConversion Factors Length
Volume Mass 2.54 cm = 1 in. 1 m = 39.4 in. 946 mL = 1 qt 1 L = 1.06
qt 454 g = 1 lb 1 kg = 2.20 lb 1 in 2.54 cm 39.4 in 1 m 39.4 in.
946 mL 1 qt 946 mL 1.06 qt 1 L 1.06 qt 454 g 1 lb 454 g 2.20 lb 1
kg 2.20 lb 2.54 cm 1 in and
Slide 56
Accuracy vs. Precision Random errors: reduce precision Good
accuracy Good precision Poor accuracy Good precision Poor accuracy
Poor precision Systematic errors: reduce accuracy
(person)(instrument)
Slide 57
Precision Accuracy reproducibility check by repeating
measurements poor precision results from poor technique correctness
check by using a different method poor accuracy results from
procedural or equipment flaws.
Slide 58
Errors Systematic Errors in a single direction (high or low)
Can be corrected by proper calibration or running controls and
blanks. Random Errors in any direction. Cant be corrected. Can only
be accounted for by using statistics.
Slide 59
Accuracy Precision Resolution subsequent samples time offset
[arbitrary units] not accurate, not precise accurate, not precise
not accurate, precise accurate and precise accurate, low resolution
-2 -3 0 1 2 3
Slide 60
SI Prefixes kilo-1000 deci- 1 / 10 centi- 1 / 100 milli- 1 /
1000 Also know 1 mL = 1 cm 3 and 1 L = 1 dm 3
Slide 61
SI System for Measuring Length Unit Symbol Meter Equivalent
_______________________________________________________________________
kilometerkm 1,000 m or 10 3 m meter m 1 m or 10 0 m decimeterdm 0.1
m or 10 -1 m centimetercm 0.01 m or 10 -2 m millimetermm 0.001 m or
10 -3 m micrometer m 0.000001 m or 10 -6 m nanometernm 0.000000001
m or 10 -9 m The SI Units for Measuring Length Zumdahl, Zumdahl,
DeCoste, World of Chemistry 2002, page 118
Slide 62
Practice Measuring 4.5 cm 4.54 cm 3.0 cm Timberlake, Chemistry
7 th Edition, page 7 cm 0 12345 0 12345 0 12345
Slide 63
Implied Range of Uncertainty 5 64 3 Implied range of
uncertainty in a measurement reported as 5 cm. 5 64 3 Implied range
of uncertainty in a measurement reported as 5.0 cm. Dorin, Demmin,
Gabel, Chemistry The Study of Matter 3rd Edition, page 32 5 64 3
Implied range of uncertainty in a measurement reported as 5.00
cm.
Slide 64
750 740 760 Here is a final example, with the vernier at yet
another position. The pointer points to a value that is obviously
greater than 751.5 and also less than 752.0. Looking for divisions
on the vernier that match a division on the scale, the 8 line
matches fairly closely. So the reading is about 751.8. In fact, the
8 line on the vernier appears to be a little bit above the
corresponding line on the scale. The 8 line on the vernier is
clearly somewhat below the corresponding line of the scale. So with
sharp eyes one might report this reading as 751.82 0.02. This
"reading error" of 0.02 is probably the correct error of precision
to specify for all measurements done with this apparatus. 5 0 10
http://www.upscale.utoronto.ca/PVB/Harrison/Vernier/Vernier.html
Slide 65
How to Read a Thermometer (Celcius) 10 5 0 4.0 o C 10 5 0 8.3 o
C 100 50 0 64 o C 5 0 3.5 o C
Slide 66
0oC0oC 10 o C 20 o C 30 o C 40 o C 50 o C 60 o C 0oC0oC 1oC1oC
2oC2oC 3oC3oC 4oC4oC 5oC5oC 6oC6oC 0oC0oC 5oC5oC 10 o C 15 o C 20 o
C 25 o C 0oC0oC 20 o C 40 o C 60 o C 80 o C 100 o C 0oC0oC 20 o C
40 o C 60 o C 80 o C 100 o C Record the Temperature (Celcius) A B C
D E 30.0 o C 3.00 o C19.0 o C 48 o C 60. o C
Slide 67
Rules for Counting Significant Figures 1. Nonzero integers
always count as significant figures. 2. Zeros: There are three
classes of zeroes. a.Leading zeroes precede all the nonzero digits
and DO NOT count as significant figures. Example: 0.0025 has ____
significant figures. b.Captive zeroes are zeroes between nonzero
numbers. These always count as significant figures. Example: 1.008
has ____ significant figures. c.Trailing zeroes are zeroes at the
right end of the number. Trailing zeroes are only significant if
the number contains a decimal point. Example: 1.00 x 10 2 has ____
significant figures. Trailing zeroes are not significant if the
number does not contain a decimal point. Example: 100 has ____
significant figure. 3.Exact numbers, which can arise from counting
or definitions such as 1 in = 2.54 cm, never limit the number of
significant figures in a calculation. 2 4 3 1 Ohn-Sabatello,
Morlan, Knoespel, Fast Track to a 5 Preparing for the AP Chemistry
Examination 2006, page 53
Slide 68
Significant figures: Rules for zeros Leading zeros are not
significant. Captive zeros are significant. Trailing zeros are
significant. Leading zero Captive zero Trailing zero 0.421 4012
114.20 three significant figures four significant figures five
significant figures
Slide 69
Significant Figures Number of
QuantityCertainUncertainSignificant DigitsDigitsFigures 14.379 g1 4
3 7 9 (thousandths) 5 6.02 mL6 0 2 (hundredths) 3 120.580 m1 2 0 5
8 0 (thousandths) 6 7.5 g7 5 (tenths) 2 0.037 g3 7 (thousandths) 2
0.0370 g3 7 0 (ten-thousandths) 3 *The position of the decimal
point has nothing to do with the number of significant figures.
Ralph A. Burns, Fundamentals of Chemistry 1999, page 52
Slide 70
___ BAH TR x = Basic Algebra Solve for x. ___ x BA = TR H ___
BAH = xTR One way to solve this is to cross-multiply. BAH = xTR
Then, divide both sides by TR. The answer is 1 TR () ___1 TR ()
___
Slide 71
Solve for T 2, where P 1 = 1.08 atm P 2 = 0.86 atm V 1 = 3.22 L
V 2 = 1.43 L T 1 = 373 K P 1 V 1 T 2 = P 2 V 2 T 1 ____ T1T1
P1V1P1V1 = P2V2P2V2 T2T2 1 P1V1P1V1 () 1 P1V1P1V1 () T 2 = P1V1P1V1
______ P2V2T1P2V2T1 130 T 2 = (1.08 atm)(3.22 L)
_____________________ (0.85 atm)(1.43 L)(373 K) = K
Slide 72
A General Procedure for Solving Problems Read the problem
carefully and make a list of the knowns and the unknowns Look up
all needed information YYour lecture notes will have much, if not
all, of the needed information Work out a plan and, following your
plan, obtain an answer by carrying out the required math. Check
over your work TThis is best done by estimating your answer AAsk
yourself: Does the answer seem reasonable?
Slide 73
How to Succeed in Chemistry Learn the language Use the
illustrations Review your notes frequently Work as many problems as
possible Do NOT cram for exams.