Molecular weight of hydrated copper sulphate CuSO4.5H2O
= 63.5 + 32 + 4(16) + 5[2(1) + 16]
= 63.5 + 32 + 64 + 5[18]
= 63.5 + 32 + 64 + 90
= 249.5 g
249.5 g of CuSO4.5H2O contains 90 g of water of crystallization.
∴ Percentage of water of crystallization
= 90\over249.5×100 = 36%
Hence, percentage of water of crystallization is 36%