# What is the formula weight?

##### 1 Answer

Dec 13, 2016

This is simply a calculation of the mass of one mole of a given substance.

#### Explanation:

Let's take a random formula,

1 mole of calcium has a mass of

From where did I get the atomic masses? Did I know them from memory? (In fact I did, and you'll get to know the common ones very rapidly.) This operation is something that you will do routinely and rapidly.