1. CH110 Foundations of GENERAL, ORGANIC, & BIOCHEMISTRY
CHEMEKETA COMMUNITY COLLEGE
INSTRUCTOR: Larry Emme

2. 1st Day Stuff Who are you? Are you in the right place? GOB
CTV Introduction
Privacy waver
Course Syllabus & requirements
Who am I?

3. Thinking like a Scientist
Prologue
P.2
Scientific Method:
Thinking like a Scientist

4. Scientific Method The scientific method
is the process used by scientists to explain observations in nature.

5. Scientific Method
The scientific method involves Making Observations Writing a Hypothesis Doing Experiments Proposing a Theory

6. Features of the Scientific Method
Observations
Facts obtained by observing and measuring events in nature.
Hypothesis
A statement that explains the observations.
Experiments
Procedures that test the hypothesis.
Theory
A model that describes how the observations occur using experimental results.

7. Summary of the Scientific Method

8. Major divisions of Chemistry
General
Inorganic
Analytical
Physical
Organic
Biochemistry
Elements besides Carbon
Methods of analysis
Theory and concepts
Carbon based compounds
Chemistry of living things

9. Conversion Calculations
Chapter 1: Measurement
Units of Measurement
Significant Figures
Conversion Calculations
Density

10. Measurements in chemistry
See Handout Sheet of
Units of Measurements

11. Units of Measurement Metric SI Common Conversions Length Volume Mass
meter (m) m = 1.09 yd
liter (L) L = 1.06 qt
gram (g) kg = 2.2 lb

12. Matter Weight on earth. Matter has Mass and takes up space.
=The stuff things are made of.
(Air, water, rocks, etc..)
Matter has Mass and takes up space.
=The amount of stuff (in g’s)
(Bowling Ball > Balloon)
Matter: The stuff things are made of. Has Mass and takes up space.
Mass: The amount of stuff. Usually measured in grams. Bowling ball has more mass than
Weight on earth.
Weight on earth.
=Pull of Gravity on matter.

13. How much would you weigh
Mass Vs. Weight
How much would you weigh
on another planet?

14. Scientific notation
If a number is larger than 1
Move decimal point X places left to get a number between 1 and 10.
, ,
= x 108
The resulting number is multiplied by 10X.

15. If a number is smaller than 1
Scientific notation
If a number is smaller than 1
Move decimal point X places right to get a number between 1 and 10.
= x 10-7
The resulting number is multiplied by 10-X.

16. Examples
Write in Scientific Notation:
25 = = = =
3,210. =
2.5  10 1
 10 3
5.93 
4 
3.210  103
Do not press this on your calculator!

17. Scientific notation 1.44939 × 10-2 = 0.0144939 On Calculator
(-) 2 EE
×10
Means
×10
Change
Sign

18. Measured & Exact Numbers
from counting or by definition
12 coins per package
12 coins
1 package
1 package
12 coins =
12 coins
1 dozen coins
1 dozen coins
12 coins =

19. Measured & Exact Numbers
Measured Numbers =
estimated using a tool
All measurements contain some uncertainty.
We make errors
Tools have limits

20. Accuracy Precision Consistency How close are we to the true value?
Truth
How well do our values agree?
Consistency

21. Length of object is between 6.7 and 6.8
Significant figures
Length of object is between 6.7 and 6.8
The next digit would be a guess.            
If use 6.76 then have error of cm

22. Significant figures Expresses accuracy & precision.
You can’t report numbers better than the method used to measure them.
6.76 units = 3 sig figures
Certain
Digits
Uncertain
Digit

23. Significant figures 3 Sig Figs
Sig Figs don’t depend on the decimal point.
255 millimeters
25.5 centimeters
2.55 decimeters
0.255 meters
decameters
3 Sig Figs

24. Significant figures: Rules for zeros
Leading zeros are not significant.
3 sig figs
Leading zero
Captive zeros are significant.
4012
4 sig figs
Captive zero
Trailing zeros behind decimal are significant.
114.20
5 sig figs
Trailing zero

25. Significant figures: Rules for zeros
32,000
Are the 0’s significant?
2 sig figs =
3 sig figs =
4 sig figs =
5 sig figs = _
32,000 or 3.2 x 104
32000 or 3.20 x 104
32000 or x 104
32000 or x 104
32000.

26. Significant figures: Rules for zeros
1025 km
2.00 mg
520
Four (Captive zeros are significant)
Three (trailing zeros behind decimal
are significant)
Three (only trailing zero behind decimal
is significant, leading zeros are not)
Two (No decimal, zero assumed insignif)

27. 1st insignificant digit
Rounding
Write with 4 Significant Figures:
becomes
> 5 round up
< 5 round down.
1st insignificant digit
becomes

28. Significant figures and calculations
An answer can’t have greater significance than the quantities used to produce it.
Example
How fast did you run if you
went 1.0 km in minutes?
speed = 1.0 km
3.00 min
= ?

29. Simplified rules for significant figures
Multiplication & Division Problems:
Do calculations.
speed = 1.0 km
3.00 min
= km
min
Look at sig figs for each value in calculation. (Constants don’t count.)
3 sig figs
2 sig figs
Report answer with same sig figs as least significant value.
= 0.33 km
min
Round off as needed.

30. Simplified rules for significant figures
Addition & Subtraction Problems:
Do calculations.
Significant to .1
1.9
20.55
Significant to .01
Look at least significant place for each value in calculation.
Report answer to least significant place.
= 20.6
Round off as needed.
Significant to .1

31. Metric prefixes Prefix Symbol Factor (multiple)
Changing the prefix alters the size of a unit.
Prefix Symbol Factor (multiple)
mega M ,000,000
kilo k ,000
deci d
centi c
milli m

32. Problem Solving Using Conversion Factors
Many problems require a change of one unit to another unit by using conversion factors (fractions).
unit1 × conversion factor = unit2

33. How many feet are there in 22.5 inches?
The conversion factor must accomplish two things:
unit1 × conversion factor = unit2
inches × conversion factor = feet
It must cancel inches.
It must introduce feet

34. The conversion factor takes a fractional form.

35. Putting in the measured value and the ratio of feet to inches produces:

36. Convert 3.7×1015 inches to miles.
Inches can be converted to miles by writing down conversion factors in succession.
in  ft  miles

37. Convert 4.51030 cm to kilometers.
Centimeters can be converted to kilometers by writing down conversion factors in succession.
cm  m  km

38. Conversion of units Examples: 10.7 T = ? fl oz 62.04 mi = ? in
5 kg = ? mg
9.3 ft = ? cm
5.7 g/ml = ? lbs/qt

39. Density Density = g At 4 o C Mass Volume g cm3 ml
1cc = 1 cm3 = 1 ml = 1 g water g
cm3 g ml
At 4 o C or
Water Urine
Air Bone
Gold Oil

40. d = m V V = m d m = V d d = 5.230 g 5.00 ml Density calculation
What is the density of 5.00 ml of serum if it has a mass of g?
d = m V
V = m d
m = V d
d = g
5.00 ml
= g ml

41. Specific Gravity is unitless.
density of substance g ml
Specific Gravity =
density of reference g ml
Reference
commonly water at 4oC
Specific Gravity is unitless.
At 4oC, density = specific gravity.

42. Commonly used to test sugar in urine. based on Specific Gravity.
Hydrometer
Commonly used to test sugar in urine.
Float height will be
based on Specific Gravity.

43. Density as a Conversion
A liquid sample with a density of 1.09 g/mL is found to weigh grams. What is the volume of the liquid in mLs?
Identify any conversion factors.
What is unique to the problem?
7.453 g
1.0 ml
1.09 g
= ml
= 6.84 ml
How should the answer look?
1.09 g
1 ml
1 ml
1.09 g