I often get asked about unit conversion, and it is a common mistake made in exams and prac classes. Units are very important, your answer without a unit means absolutely nothing! So, it’s important to get it right.
In the metric system, you need to know some of the prefixes associated with orders of magnitude.
tera- (T-) | 1012 |
giga- (G-) | 109 |
mega- (M-) | 106 |
kilo- (k-) | 103 |
hecto- (h-) | 102 |
deka or deca- (da-) | 10 |
deci- (d-) | 10-1 |
centi- (c-) | 10-2 |
milli- (m-) | 10-3 |
micro- (µ-) | 10-6 |
nano- (n-) | 10-9 |
pico- (p-) | 10-12 |
You need to multiply by a factor of 1000 to go between each prefix shown above.
There are a series of tutorials below, many of which have worked examples and problems for you to try:
http://chemistry.about.com/od/convertcalculate/a/conversions.htm
http://www.tutor-homework.com/Chemistry_Help/Unit_Conversion.html