Metric Conversions
We only use metrics in Chemistry
5 kg = _______ mg
3.5 liters = _____ ml
4 cm3 = ____ ml
250 cm = _____ m
The Metric System
Compared to the English System:
Mass = ?
Volume = ?
Length = ?
Metric is based on decimals.
• Converting English units involves number
changes: miles to inches.
• Metric conversions simply involve moving the
decimal point ( a power of ten).
• Which way you move the decimal depends on
whether going from a larger unit (Kg) to
smaller (g) or the opposite.
• Big to small – move it ??
• Small to big – move it ??
Ok, the size of units is represented by
a set of prefixes!
• Kilo = 1000 of anything. That’s 3 decimal
place moves because of 3 zeros.
• Centi = .01, that’s 1/100th of something; like 1
penny is .01 of a dollar. 1cent = $0.01. That’s
2 decimal place moves.
• Milli = .001, that’s 1/1000th of something; like
1 mm = .001 of a meter. 3 decimal moves.
What are the Base units in Metric?
• Length: meter
• Volume:
• Mass: gram
• Now, you can have a Kilogram (kg), a Kilometer
(km) and a kiloliter (Kl).
• You can have a centigram (cg) a centimeter (cm)
and a centiliter (cl)
• You can have a milligram (mg), a millimeter (mm)
and a milliliter (ml).
Kilo  base unit centi  milli
3 places
2
1
• So, from Kilograms to grams, you move the
decimal 3 places to the right.
• From Kg’s to milligrams, you move it 6 places
to the right.
• From milligrams to grams, you move the
decimal 3 places to the left!
• Then, 5 kilograms = _____ mg ?
• And it works the same for all conversions !!!
Remember
• Use the conversion for a while, but learn how
to covert metric units without it.
• When converting metric problems, only the
decimal changes, NEVER the actual number.
• 4.2 kg = 4200 grams.
Try These
• Mass: 6.5 kg = ___ g 0.5 Kg = ___ g
• 550 g = ____ kg 1250 g = ___ kg
150 kg = ___ g
0.5 g = ___ kg
• Volume: 5.5 liters(l) = ___ ml
1750 L = ___ ml
0.45 L = __ ml
250 ml = ___ L
1500 ml = ___ L
750 ml = ___ L
• Length: 4 km = ___ m
2500 m = ___ km
0.40 m = ___ cm
5 m = ___ mm
* 7.5 km = ___ cm
2.5 km = ___m
500 m = ___ km
250 cm = ___ m
800 mm = ___ m
5.5 km = ___ mm
0.75 km = ___ m
6 m = ___ cm
75 cm = ___ m
Now, let’s try these !