There is a sample of calcium chloride. Some hydrous, some anhydrous. How do you find the percent that is hydrous...

There is a sample of calcium chloride. Some hydrous, some anhydrous. How do you find the percent that is hydrous given that 0.320 g of water evaporated from that sample with a mass of 2.015 g. Helpful info: 147.0140g = 1 mol CaCl2.2H2O 110.983 g = 1 mol CaCl2 This isn't a homework question. We did a lab with what we though was hydrous calcium chloride and wasn't all. This is for my bit about further investigations. Thanks