1. Measurement and the Factor Label Method
Chem 140

2. SI base units SI (Système Internationale d’Unites) adopted in 1960
Contains 7 base units:
length: meter (m)
mass: kilogram (kg)
time: second (s)
electrical current: ampere (A)
temperature: kelvin (K)
amount of substance: mole (mol)
Luminous intensity: candela (Cd)

3. Know Your Metric Prefixes
value (exp.)
value
tera- (T)
1012
1,000,000,000,000
giga- (G)
109
1,000,000,000
mega- (M)
106
1,000,000
kilo- (k)
103
1,000
deci- (d)
10-1
0.1
centi- (c)
10-2
0.01
milli- (m)
10-3
0.001
micro- (µ)
10-6
nano- (n)
10-9
pico- (p)
10-12

4. Derived units: speed 1 m s-1 1 meter… …in 1 second speed (velocity) 1020 30 40 60 70 80 90 50
1 meter…
…in 1 second
1 m s-1
speed (velocity)

5. Derived units: acceleration
speedometer
m s-1
Start

6. Derived units: acceleration
1 meter per second
per second 1
1 m s-2
speedometer
m s-1
After 1 second

7. Acceleration – 6 m = s2 50 m/s… …to 20 m/s… …in 5 s change in speed
time =
–30 m s  1
5 s
acceleration = =
– 6 m s2

8. Other derived units Force (newton, N): kg m s-2
Work, energy (joule, J): kg m2 s-2
Power (watt, W): kg m2 s-3
Pressure (pascal, Pa): kg m-1 s-2
Volume: m3
Density: kg m-3

9. Metric to English (Without Too Much Memorizing)
1 inch = 2.54 cm
1 gallon (US) = 231 in3
1 lb. = g
°C = (°F – 32) x 5/9
°F = (°C x 9/5) + 32
You can figure out many
other conversions from
these basic (exact) ones

10. Factor-label method (on board)
Convert 65 mph to m s-1, using the information on the previous slide, and english-to-english conversions.
A car gets 35 mpg fuel mileage. What’s this in km/L?
cubic meters to cm3

11. Volume What is the volume of a cube 0.1 m (1 dm) on a side, in m3?
Also called a “liter” (L)

12. Volume
What is the length of each side of a cube with a volume of 1 mL?
0.001 L
= m3
= (0.01)3 m3
= 0.01 m (1 cm) on a side

13. 1 m3 = 1 kL Length and Volume 1 Mg of water 1 cm3 1 kg of water = 1 mL10 20 30 40 60 70 80 90 50
1 dm3
= 1 L
1 cm3
= 1 mL
1 kg of water
1 g of water
1 Mg of water

14. Volume and Mass Linear Cubic Liters Water 1 m 100 m 1 m3 100 m3 1 kL
1 Mg
1 dm
10-1 m
1 dm3
10-3 m3
1 L
100 L
1 kg
1 cm
10-2 m
1 cm3
10-6 m3
1 mL
10-3 L
1 g
1 mm
10-3 m
1 mm3
10-9 m3
1 µL
10-6 L
1 mg