Question

a hydrate of CoCl2 with a mass of 6.00g is heated strongly. After cooling, the mass of the anhydrate is 3.27g.
a) How many grams of H2O were lost from the hydrate?

Answer 1

The mass lost will be equivalent to the mass of water in the hydrate. Thus,
mass of water = 6.00 - 3.27
= 2.73 grams of water were lost.