Question

What substance is added to turn the white copper sulphate to blue copper sulphate?​

Answer 1

WATER is added to turn white copper sulphate into blue copper sulphate.This is due to the presence of water of crystallisation.

Answer 2

Answer:

The white copper sulphate changes to blue copper sulphate with the addition of water.

Explanation:

Copper sulphate is white in the anhydrous form (with no water of crystallization) and changes to blue copper sulphate as water is added to it. It forms a blue crystalline structure often called blue vitriol with 5 molecules of water or pentahydrate. When water is added to it, it forms a bubble to liberate heat and crystallizes.