Question

crystal of copper sulphate are blue in colour ​

Answer 1

Answer: The blue coloured copper sulphate crystals turns white due to the loss of water molecules. The formula of copper sulphate is CuSO4. 5H2O. When copper sulphate is heated, it looses water molecules and hence it looses blue colour

Answer 2

In compounds copper sulphate, the blue colour is due to the light energy being used to promote or excite electrons that are in the atom of the copper when it's combined with other things such as the sulphate or carbonate ions and so on.

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