Question

What happens when a copper rod is dipped in an iron sulphate solution?
A. Copper displaces iron
B. Blue color of copper sulphate is obtained
C. No reaction takes place
D. Reaction is exothermic

Answer 1

Hint: Generally more reactive metals are going to replace the less reactive metals in the molecules. We can find which metal can replace what metal by using electrochemical series. In electrochemical series the metals are arranged according to their reduction potential values.

Complete Solution :
- In the question it is given what happens when a copper rod is dipped in iron sulphate solution.
- We have to find which option is correct, when copper rod is dipped in iron sulphate solution.
- As per the electrochemical series the reduction potential of copper is high (more) when compared to iron.
- Thus the copper cannot displace the iron from its salt solution due to its high reduction potential value.
- Therefore there is no reaction when copper rod is dipped in iron sulphate solution.
So, the correct answer is “Option C”.

Note: To replace a metal from its original composition, we need a metal which has less reduction potential value. We can replace copper by using iron from its salt because iron has low reduction potential when compared to copper.
The reduction potential of copper is = 0.34
The reduction potential value of iron = - 0.44
- Reduction potential value decides which metal is going to accept electrons very easily and which metal is going to donate electrons very easily.