Question

In a cell, the following reaction takes place: $Fe + CuS{O_4} \to FeS{O_4} + Cu$. The cell can be represented as:

Answer 1

The given reaction $Fe + CuS{O_4} \to FeS{O_4} + Cu$ is an example of a displacement reaction. In this reaction, iron replaces copper present in copper sulphate as iron is highly reactive metal. Iron replaces copper in copper sulphate by giving up two electrons and gets oxidized and forms new compound ferrous sulphate.

Complete answer:
When an iron nail is dipped in a solution of copper sulphate in water, the iron displaces the copper and turns the blue coloured solution of copper sulphate into a light green colour solution of iron sulphate. The cathode and anode are separated by two bars which represent a salt bridge. The anode should be placed on the left side and the cathode should be placed on the right side. The right hand half reaction shows reduction reaction and the left hand half reaction shows oxidation reaction. $Fe$ gets oxidized to $F{e^{ + 2}}$ and $CuS{O_4}$ is reduced to $Cu$ in the given reaction. So, we can say that iron acts as anode and copper acts as cathode in the reaction. So, the correct representation of the cell will be: $Fe|FeS{O_4}||CuS{O_4}|Cu$
Therefore, the cell can be represented as $Fe|FeS{O_4}||CuS{O_4}|Cu$

Note:
The cell reaction describes the chemical change. Its reaction equation is the sum of equations for the reactants of two electrodes with the cancellation of electrons. A galvanic cell converts energy which is released by a spontaneous chemical reaction into electrical energy. An electrolytic cell uses electrical energy from an external source to drive a non-spontaneous chemical reaction.