Just a Quick Recap on Quantities and Unit Conversions

Last class we learned the fundamental basics towards futher understanding of chemistry. First we learned that quantities always have two parts-the number and the unit.
                                                    ex. 15 m, 40 s

The units we use derive from the SI (Système Internationale) which is a French system that is based upon using powers of ten. The following are the units:

Conversions aren't as complicated as we think! With the help of the "magic one", conversions are made simpler. Also, when converting, we always want to put the SAME units across from each other. That way, they are able to cancel each other out:

                                                          ex. 500cm into m
                                                                 5
                                                                 500 cm x   1 m       
                                                                     1         1 100 cm   = 5 m
Here are more examples using scientific notation: