Question

The standard reduction potentials of zinc, cadmium and copper are $-0.76V,-0.4V$ and $0.34V$ respectively. Select the correct statement.

• A. Copper can reduce both $Z{n}^{2+}$ and $C{d}^{2+}$ ions.
• B. Cadmium can reduce both $Z{n}^{2+}$ and $C{u}^{2+}$ ions.
• C. Zinc can reduce $C{u}^{2+}$ ion but cannot reduce $C{d}^{2+}$ ion.
• D. Zinc can reduce both $C{u}^{2+}$ and $C{d}^{2+}$ ions.

Answer 1

The correct option is D Zinc can reduce both $C{u}^{2+}$ and $C{d}^{2+}$ ions.

Given that the standard reduction potentials of zinc, cadmium, and copper are $-0.76V,-0.4V$ and $0.34V$ respectively.

Hence, the standard reduction potential of zinc $<$ standard reduction potential of copper.

Also, the standard reduction potential of zinc $<$ standard reduction potential of cadmium.

Therefore, both $C{u}^{2+}$ and $C{d}^{2+}$ ions get reduced more easily as compared to $Z{n}^{2+}$.

Hence, zinc can reduce both $C{u}^{2+}$ and $C{d}^{2+}$ ions.