The Metric System & Unit
Conversions
The Metric System…
We use this system in all science
courses
Everything is based on powers of 10.
There is a different unit for every kind of
measurement…
Fundamental Units of Measure
(SI units)
Length
Meter
m
Mass
Kilogram
kg
Time
Second
s
Temperature
Kelvin
K
Amount of
Substance
Mole
mol
Use these to convert
metric units
(Mega-) 1 Mm = 1 x 106 m
(kilo-)
1 km = 1000 m
Base = m, (grams, Liters, etc…)
(deci-) 10 dm = 1 m
(centi-) 100 cm = 1 m
(milli-) 1000 mm = 1 m
(micro-) 1 x 106 m = 1 m
Yellow means you need to memorize
Metric System (continued)
All other units for everything can be
derived from the fundamental units!
Example: Volume is a function of
cubic length…
– 1 mL = 1 cm3
English to Metric…
Some conversions from English to Metric
– 1 lb = 453.6 g
– 1 in = 2.54 cm
– 1 yd = 0.91 m
– 1 mi = 1.609 km
– 1 qt = 0.95 L
– 1 kg = 2.2 lbs
– Write these down where you can find them.
You do not have to memorize these but you
need to be able to find them.
Can you estimate for metric?
Length of a soccer field
– Meter (m)
Length of Avon
– Kilometer (km)
Mass of pencil eraser
– Gram (g)
Mass of human hair
– Milligram (mg)
Mass of human
– Kilogram (kg)
Practice…
Convert the following…
1 6.7 km to m.
2 1.00 mL to L.
3 15.6 cm to m.
4 10.0 mi to m.
5 12.5 lbs to kg.
Temperatures
Boiling Temp of H2O
Freezing Temp of H2O
Absolute Zero
212
100
373
32
0
273
-459
-273
0
°F
°C
K
Temperature Formulas
Formulas
– C = (F - 32)5/9, F = [(9/5)C] + 32
– K = C + 273, C = K - 273
Scientific Notation
We use extremely small and extremely
large numbers in chemistry and physics
courses.
We must be able to convert these
numbers into a manageable form.
0.0000046 =
4.6x10-6
520,000 =
5.2x105
Practice
Write the following in scientific notation
0.000000046 km
250,000,000 m
35,024,000 miles
0.0000502 g
4.2x106 g
5.7x10-3 L
Multiply & Divide with Scientific
notation
When you multiply numbers in scientific
notation you multiply the numbers and add
the exponents.
4
7
4x10 6x10 
When you divide numbers in scientific
notation you divide the numbers and
subtract the exponents.
5

8x10  
4 x10 
3
Unit Conversion Homework
and
Metric Square Puzzle