Question

The EMF of the cell,$\mathbf{Ni|N}\mathbf{i}^{\mathbf{2 +}}\mathbf{||C}\mathbf{u}^{\mathbf{2 +}}\mathbf{|Cu}$ is 0.59 volt. The standard electrode potential (reduction potential) of copper electrode is 0.34 volt. The standard electrode potential of nickel electrode will be

• A. 0.25 volt
• B. – 0.25 volt
• C. 0.93 volt
• D. – 0.93 volt

Answer 1

Answer: (B)

– 0.25 volt

Answer 2

$E_{cell}^{0} = E_{{Re}d}^{0}(RHS) - E_{{Re}d}^{0}(LHS)$

$\mathbf{=}\mathbf{E}_{\mathbf{C}\mathbf{u}^{\mathbf{2 +}}\mathbf{/Cu}}^{\mathbf{0}}\mathbf{-}\mathbf{E}_{\mathbf{N}\mathbf{i}^{\mathbf{2 +}}\mathbf{/Ni}}^{\mathbf{0}}$

i.e. $0.59 = 0.34 - E_{Ni^{2 +}/Ni}^{0}$

or $E_{Ni^{2 +}/Ni}^{o} = 0.34 - 0.59 = - 0.25Volt$