Question

what changes can be observed in crystallisation of cuso4

Answer 1

Copper sulphate crystals(CuSO4.5H2O), contain water of crystallisation so the crystals are hydrated and blue in colour.When heated strongly,they looses the water of crystallisation and turns white and become anhydrous(CuSO4)
1.Water vapours that released condense on the cooler part of the test tube.
2.Blue crystals in the test tube turns white.
3. On heating following reaction takes place,
CuSO4.5H2O -----------------> CuSO4 + 5H2O
Blue crystals Anhydrous
It is observed that if white powder is allowed to cool and water drops are added then they regain blue colour as they become hydrous again.

Hope that helps u!!