1. Introduction to the Metric System
ACS
Ms. Grogan

2. History Created during French Revolution in 1790
French King overthrown
National Assembly of France sets up new government
French Academy of Science told to design new system of weights and measures
Lavaiosie appointed to head committee

3. History Called Systeme International d’Unitès, Revised periodically
or SI - International System of Units
Revised periodically
by International Bureau of Weight and Measures

4. Customary Units of Measurement
The English System
a collection of functionally unrelated units
Difficult to convert from one unit to another
Ex. 1 ft = 12 inches = 0.33 yard = 1/5280 miles
Customary Units
length - inch, foot, yard, mile
weight/mass - ounce, pound
volume - teaspoon, cup, quart, gallon
temperature - degrees Fahrenheit
time - minutes, hours

5. Advantages of Using the Metric System
Universal - used everywhere
by all scientists to communicate
by all industrialized nations
except United States
U.S. loses billions of dollars in trade

6. Advantages of Using the Metric System
Simple to use
A few base units make up all measurements
length - meter
mass - grams
volume - liters
temperature – degrees Celsius
time - seconds

7. Advantages of Using the Metric System
There is only one unit of measurement for each type of quantity
To simplify things, very small and very large numbers are expressed as multiples of the base unit.
Prefixes are used to represent how much smaller or larger the quantity is compared to the base unit.
Easy to convert from one unit to another
shift decimal point right
shift decimal point left

8. Advantages of Using the Metric System
Same set of prefixes for all units
Greek - multiples of the base
kilo × the base
hecto × the base
deka - 10 × the base
Latin - fractions of the base
deci - tenths of the base
centi - hundredths of the base
milli - thousandths of the base
Mnemonic: “Kids Have Dropped Over Dead Converting Metrics.”

9. Metric Prefixes

10. Units of Length Length - the distance between two points
standard unit is meter (m)
long distances are measured in km
Measured using a meter stick or ruler

11. Prefixes and Units of Length
centimeter - cm
1 m = 100 cm
1 cm = 1/100th m
millimeter - mm
1 m = 1000 mm
1 mm = 1/1000th m
10 mm = 1 cm
measures very small lengths
kilometer - km
1 km = 1000 m
1 m = 1/1000th km
measures long distances

12. Measuring Mass Mass - the quantity of matter in an object
standard unit is gram (g)
Measured using a digital scale or triple beam balance

13. Measuring Volume and Capacity
Volume - the amount of space occupied by an object
standard unit is liter (L)
1 L = 1000 ml = 1000 cm3 = 1 dm3
Measured using a graduated cylinder
Capacity - a measure of the volume inside a container

14. Prefixes and Units of Volume
Liter - L
1 L = 1000 milliliters
1 L = 1000 cubic centimeters = 1000 cm3
milliliter - mL
measures small volumes
1 mL = 1 cubic centimeter
1000 mL = 1 Liter
1 mL = 1/1000th liter
kiloliter - kL
measures large volumes
1 kL = 1000 L

15. Measuring Volume Measured with a graduated cylinder
Determine value of each mark on the scale
Read scale using the lowest position of the meniscus
Measure the meniscus at eye level from the center of the meniscus.
In the case of water and most liquids, the meniscus is concave. Mercury produces a convex meniscus.

16. Displacement Displacement Amount of water an object replaces
Equal to its volume

17. Volume of a Solid, Irregular Object
Displacement - amount of water an object replaces
Procedure
Place graduate beaker beneath spout
Fill the overflow can with water until water begins to spill
Empty the excess water
Place object to be measured into the overflow can
Remove when water stops flowing out of the can
Measure the displaced water using a graduated cylinder.

18. Volume of a Solid, Irregular Object
Displacement
Calculate the difference between the initial and final volume measurement.

19. Volume of a Solid, Regular Object
Volume - length x width x height
V = 2.8 cm x 3.2 cm x 2.5 cm
V = 22.4 cm3
Measured with a ruler

20. Calculating Density
Density - a specific property of matter that is related to its mass divided by the volume.
D=M/V
the ratio of mass to volume
used to characterize a substance
each substance has a unique density
Units for density include:
g/mL
g/cm3
g/cc

21. Measuring Time
Time
metric unit is second (s)

22. Measuring Temperature
Temperature - the degree of “hotness” of an object
standard unit is celsius (°C)
measured with a thermometer

23. Temperature Conversions
Conversion Between Fahrenheit, Celsius, and Kelvin
Example:
Convert 75 ºC to ºF
Convert -10 ºF to ºC

24. Measurement Unit Conversion
You can convert between units of measurement
within the metric system
between the English system and metric system

25. Conversion and the Metric System
ACS
Ms. Grogan

26. Measurement Unit Conversion
You can convert between units of measurement
within the metric system
between the English system and metric system

27. Unit Conversion
Let your units do the work for you by simply memorizing connections between units.
Example: How many donuts are in one dozen?
We say: “Twelve donuts in a dozen.”
Or: 12 donuts = 1 dozen donuts
What does any number divided by itself equal?
ONE!

28. Unit Conversion This fraction is called a unit factor
Multiplication by a unit factor does not change the amount - only the unit.
Example: How many donuts are in 3.5 dozen?
You can probably do this in your head but try it using the Factor-Label Method.

29. Unit Conversion Rules Start with the given information…
Then set up your unit factor…
See that the original unit cancels out…
Then multiply and divide all numbers…

30. Unit Conversion Practice
Example: Convert 12 gallons to units of quarts.

31. Unit Conversion Practice
Example: Convert 4 ounces to kilograms.