Question

Why does the colour of copper sulphate solution change whenan iron nail is dipped in it?

Answer 1

because iron and copper sulphate react with each other to form iron sulphate + copper due to which colour changes. It can be represented in the form of following equation:- Fe + CuSo4 ---------> FeSo4 + Cu

Answer 2

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When an iron nail dipped in the copper sulphate solution than iron displaces copper from the copper sulphate because iron is more reactive than copper. Therefore the colour of the copper sulphate solution changes.

The reaction involved here is:

Fe (s) + CuSO4 (aq) → FeSO4 (aq) + Cu (s)