Question

A solution of ........ in water is blue in colour​

Answer 1

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. ... Thus other colours are absorbed & you see only blue.

Answer 2

Hey mate here is your answer


Copper Sulphate (CuSO4)

Hoppe helps!!!!
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