Metric ConversionsWe only use metrics in Chemistry

5 kg = _______ mg3.5 liters = _____ ml

4 cm3 = ____ ml250 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: liter• 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 150 kg = ___ g • 550 g = ____ kg 1250 g = ___ kg 0.5 g = ___ kg

• Volume: 5.5 liters(l) = ___ ml 1750 L = ___ ml 0.45 L = __ ml250 ml = ___ L 1500 ml = ___ L 750 ml = ___ L

• Length: 4 km = ___ m 2.5 km = ___m 0.75 km = ___ m2500 m = ___ km 500 m = ___ km 6 m = ___ cm0.40 m = ___ cm 250 cm = ___ m 75 cm = ___ m5 m = ___ mm 800 mm = ___ m * 7.5 km = ___ cm 5.5 km = ___ mm

Now, let’s try these !