when CuSO4dissolved in water, no chemical reaction takes place since no new substance is getting formed.Thus it is a physical change. The dissolution of Zinc granules in dil. HCl is a chemical change because zinc reacts with hydrochloric acid to form zinc chloride and hydrogen gas is liberated. The reaction is : →Zn+2HCl→ZnCl 2+H2 ( all numericals comes down of the no I cant write it down)