Question: how many moles of water in cuso4?
Answer: A mole of CuSO4•5H2O contains 5 moles of water (which corresponds to 90 grams of water) as part of its structure. Therefore, the substance CuSO4•5H2O always consists of 90/250 or 36% water by weight. The water is a definite part of the structure of the compound, and the substance should not be considered to be “wet.”