What is the voltage required to electrolytically refine impure copper of activity 𝑎_𝐶𝑢 = 0.9 (Raoultian standard state) to pure copper at 300 K?

Given: Gas constant R = 8.314 J mol^{– 1} K^{– 1}, and Faraday’s constant F = 96500 C mol ^-1.

(A) 1.36 mV                (B) 2.72 mV               (C) 0 mV                             (D) 5.44 mV