hard question, please help

Question

Cobalt (II) chloride is commonly obtained from chemical supply houses as a hydrate with the formula CoCl₂* 6 H₂O. An analysis showed that 25.0 g of this hydrate contains 11.3 g of water. What is the percent water by weight in this hydrate?

Answer 1

11.3 g H2O/25.0 g total = 0.452 = 45.2% H2O

Answer 2

Hi Brian, you can calculate the percent water by using:

Percent of water = (mass of water/mass of hydrate ) x100

= (11.3 g/25.0g) x 100

= 45.2%.