At 298K and an ion activity of 0.005, the potential of Cu ^ 2 + | Cu is + 0.2712V.

At 298K and an ion activity of 0.005, the potential of Cu ^ 2 + | Cu is + 0.2712V. Calculate the standard potential of the copper electrode.

To find the standard potential of a copper electrode based on its activity and potential at this activity, we use the Nernst equation:

E = E0 + 2.303 * R * T / (n * F) * log a (Cu (2+))

R – universal gas constant = 8.314 J / mol K

F – Faraday number = 96500 C / mol

T – absolute temperature = 238 K

E0 – standard potential of copper

0.2712 V = E0 + 2.303 * 8.314 * 298 / (2 * 96500) * log (0.005)

0.2712 = E0 + 0.059 / 2 * log (0.005)

0.2712 = E0 -0.06788

E0 = 0.2712 + 0.06788 = +0.339 B