Question

why does the colour of copper sulphate solution change when an iron nail dipped in it .​

Answer 1

Explanation:

When an iron nail immersed in the solution of copper sulphate than iron displaces copper from the solution of copper sulphate because iron is more reactive than copper. Therefore copper sulphate solution colour changes from blue to pale green.

Answer 2

Answer:

iron nail displaces copper from it's solution because iron is more reactive than copper