The heat of hydration is the enthalpy change when 1 mole of anhydrous salt reacts with a specific amount of water to form the hydrated salt. In this case, 1 mole of anhydrous copper II sulfate reacts with water to form 5 moles of hydrated copper II sulfate. The enthalpy change for this reaction is given as -92.2 kJ/mol.Since the reaction involves 1 mole of anhydrous copper II sulfate, the heat of hydration for this reaction is simply the enthalpy change for the reaction:Heat of hydration = -92.2 kJ/mol