06. Converting between mass, moles and molecules

Converting between mass and moles:

Use this formula to convert between moles of a substance and mass.

For example: How many moles are in 72g of water?

First find the relative formula mass for water = 16 + 1 +1 = 18g/mol

Secondly cover up amount in the triangle above and you are left with amount = mass / relative formula mass

Thirdly carry out the calculation: amount = 72 / 18 = 4 mol