CuSO45H20 is blue in colour while CuSO4 is colourless. Why?

In CuSO, :SH,0, water acts as ligand and causes arystal field spliting. Hence, d-d
transition is possible thus CuSO, :SH,0 is coloured. In the anhydrous CuSO4 due to the
absence of water (ligand), crystal field splitting is not possible and hence, itis colourless.