Question

Add a nail in CuSO4 Sodium, the colour of CuSO4 disappears why?

Answer 1

The iron nail displaces the Cu from the copper sulfate solution.  This results in the color of CuSO4's disappearance. Copper is less reactive than iron.

Answer 2

Answer and Explanation

Add a nail in CuSO4 Sodium, the color of CuSO4 disappears because iron (Fe) is more reactive than the copper (Cu). Hence, it replaces copper. The color of copper sulphate (CuSO4) is blue but when iron (Fe) replaces its place, it becomes iron sulphate (FeSO4) which is the light green color.

When we add an iron nail in copper sulfate solution (CuSO4) the reaction takes place between them which is as Fe+CuSO4->FeSO4+Cu. Due to more reactivity of iron, replacement happens and FeSO4 forms which is light green in color. Therefore, in this reaction color changes from blue to green.