Question

Determine the percent water in CuSO4∙5H2O to three significant figures

Answer 1

Answer: 36.1%

Explanation: The molar mass of the complete molecule, CuSO4*5H2O is 249.6 g/mole. The molar mass of just the water (5H20) is 90 g/mole. Assume 1 mole of CuSO4*5H2O, the percent water would be:

90g H2O/249.6g CuSO4*5H2O = 0.361 or 36.1%