1. Chapter 2 Analyzing Data
International System of Units (S.I.)
Le Systeme International d`Unites.
Table 1 page 33 SI base units
Mass vs. Weight
Mass – kilogram (kg), measures the amount of matter.
Weight – is the force of gravity on a sample of matter.

2. Derived Units Combination of two or more SI base units.
Volume = amount of space occupied by an object.
length x width x height = (m3)
Liquid Volume – (mL)
Density = ratio of mass to volume.
D = m/v

3. Metric System The International System of Units Standard
Based upon tens or decimal places.
Used throughout the world.

4. Table of Prefixes Prefix Abbrev. Meaning Tera- T 1012 Giga- G 109
Mega- M 106
kilo- k 103
hecto- h 102
deca- da 101
Base Units - meter, liter, gram, or second
deci- d
centi- c
milli- m
micro- µ
nano- n
pico- p

5. Conversion Factors
Ratio derived from the equality between two different units, that can be used to convert from one to the other.
1 dollar = 4 quarters

6. 2.2 Dimensional Analysis
Mathematical technique to help solve problems using conversion factors.
How many dollars do you have if you have 45 quarters in your bag?

7. Scientific Notation Scientific Notation or Exponential Notation
Written as the product of two numbers.
Coefficient and a power of 10.
n. x 10e
Where n is a digit e is the exponent.

8. Proportions Directly Proportional Inversely Proportional
Dividing one quantity by the other gives a constant value.
Inversely Proportional
Product of two quantities are constant values.

10. Metric Conversions
Convert 50 kg to g.
Convert 30 cm to m.

11. Metric Conversions
Identify the conversion factors needed to convert cm to mm.
Identify the conversion factors needed to convert cm3 to mm3.

12. Conversion of Cubic Units of Volume
Practice
1) 1.2 x 10-3 nm3 = ? mL
2) 1.4 x 10-2 m3 = ? mm3

13. Exit Problem
Before you leave you must complete the following conversion and place it in the folder on the teacher desk.
2.25 x10 -5 km3 = ? µm3

14. 2.3 Uncertainty in Data Accuracy Precision
How close a single measurement comes to the actual dimension or true value.
Precision
How close several measurements are to the same value.

16. Percentage Error Error in Measurement
Measurements always contain some degree of error.
+/- .5 error

17. Significant Figures
In a measurement include all the digits that are known precisely plus one last digit that is estimated.
Rules for Significant Figures

19. Significant Figures Rules for significant digits:
All non-zero digits are significant.
Zeroes in between two non-zero digits are always significant.
Zeroes after a non-zero digits are only significant if the number has a decimal.
Zeroes after non-zero digits are not significant if the number has no decimal.
Zeroes in front of non-zero digits are never significant.

20. Sig Figs in Calculations
An answer can’t be more precise than the least precise measurement from which it was calculated.
Multiplication & Division
Round all answers to the fewest sig fig.
Addition & Subtraction
Round to the same number of decimal places as the measurement with the least precision.

21. Sample Problems 1) (5.232x106 mm )(4.33x102mm)= 2)
3) 4.33x102cm + 1.2x102cm=
4) 7.90 kg – 4.2 kg=

22. Word Problems Using Dimensional Analysis
Round all answers to the number of significant figures as the given.

23. p.p#1
If 1500 white blood cells (WBC) are lined up side by side they would form a row 1.0 in long. What is the average diameter in micrometers of a single WBC? (1in = 2.54cm)

24. p.p. #2
A radio wave travels miles per second. How many kilometers will the wave travel in one microsecond?
(1 mi = 1.61 km)

25. p.p. #3
Eggs are shipped from a poultry farm in trucks. The eggs are packed in cartons of one dozen eggs each; the cartons are placed in crates that hold 20 cartons each. The crates are stacked in the trucks, 5 crates across, 25 crates deep, and 25 crates high. How many eggs are in 5 truckloads?
1carton = 12eggs 1truck = 3125 crates
1 crate = 20 cartons

26. p.p. #4
Iodine is an essential nutrient in our diet that prevents goiter. To obtain enough iodine, we can use iodized salt, which is .01%NaI by mass. How many kilograms of NaI should be added to 1000kg of table salt to achieve this percentage of NaI?

27. p.p. #5
The antlers of a deer are 50% Ca by mass. The calcium comes from leaves that the deer eat. The leaves are .07%Ca by mass. How many kilograms of leaves would a deer need to eat in order to provide enough calcium to grow antlers weighing 3 kilograms?