Question

What is the standard cell potential for the reaction with $K=1$ (equilibrium constant)

• A. One
• B. Zero
• C. 2.303
• D. Infinity

Answer 1

Answer: (B)

The relationship between cell potential and the equilibrium constant. We know.
$\Delta G=-RT\ln k=-nF{E}^{\circ }$
$\Delta G=-2.303RT\log k=-nF{E}^{\circ }$
$\log K_f=\frac{nF\times E^{\circ }}{RT\times 2.303}$
$\log (1)=\frac{n}{0.059}\times E^{\circ }(n=1)$
$\Rightarrow 0\times 0.059=E^{\circ }$
$\Rightarrow E^{\circ }=$ zero