CuSO4---->Cu+2 + SO4-2

What next? Cu+2 + H2O or SO4-2 + H2O??

You should have been a Kc constant for a certain reaction, or more. Depending on what you were given, write an equation and use the Kc given to you. If you could post the original question with all the given details, it sure would be easier to help you.