The electrode potential of any cell compared to standard hydrogen electrode is given by the Nernst equation, . Where E⁰ is the standard cell potential, R is the universal gas constant, T is the temperature in Kelvin, F is the Faraday constant, [Mⁿ⁺] is the concentration of the electrolyte.

For a Daniell cell, the cell potential is given in the following equation after converting the natural logarithm to the base 10 and substituting the values of R, F and T = 298 K –

E_cell = - .

At equilibrium,

E_cell = 0. So, E^Ө_cell =

K_c = [Zn²⁺]/[Cu²⁺]

So the equation can also be written as

E^Ө_cell =

From these equations, it can be calculated that (ii) and (iii) are correct.