Question

An Iron rod is immersed in a solution of Copper Sulphate. What will happen to the Iron rod?

Answer 1

• When an Iron rod is immersed in a solution of Copper Sulphate it forms a pale green solution of the Ferrous Sulphate.

$$\begin{gathered} {\mathbf{CuSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{aq}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{Fe}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{}{\mathbf{FeSO}}_{\mathbf{4}}\mathbf{}\mathbf{\left(}\mathbf{aq}\mathbf{\right)}\mathbf{}\mathbf{+}\mathbf{}\mathbf{Cu}\mathbf{}\mathbf{\left(}\mathbf{s}\mathbf{\right)} \\ \mathbf{Copper}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Iron}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Iron}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Copper} \\ \mathbf{Sulphate}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{Sulphate} \end{gathered}$$

• When an Iron rod is dipped in Copper Sulphate solution, a brown coating of Copper is formed on the surface of the Iron and the colour of the Copper Sulphate solution changes from blue to pale green.
• The reaction shows that Iron is more reactive than Copper because it displaces Copper from the Copper Sulphate solution.