Question

Anhydrous copper sulphate greyish white if kept in open in the mouth of july changes to the blue colours why​

Answer 1

because it reacts with the oxygen present in the air

Answer 2

Because the anhydrous copper sulphate is changed into hydrous copper sulphate and its formula become CuSO4 and the colour of CuSO4 is blue in colour. Hence it change into blue colour.

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