Question

What is the Eº꜀ₑₗₗ for the reaction
Cu² (aq) Sn² (aq) ⇋ Cu(s) Sn⁴ (aq)
at 25ºC if the equilibrium constant for the reaction is 1 × 10⁶ ?
(a) 0.5328 V (b) 0.3552 V
(c) 0.1773 V (d) 0.7104 V

Answer 1

the Eº꜀ₑₗₗ for the given reaction  at 25ºC if the equilibrium constant for the reaction is 1 × 10⁶ is 0.1773 V

- the formula for Eº꜀ₑₗₗ can be written as

    Eº꜀ₑₗₗ = (2.303RT/nF) log K

- At 25°C, this formula becomes

   Eº꜀ₑₗₗ = (0.0591/n) log K

- Here, n = 2 and K = 10⁶

-So, Eº꜀ₑₗₗ = (0.0591/2) log 10⁶

       Eº꜀ₑₗₗ = (0.0591/2) × 6 × log 10

       Eº꜀ₑₗₗ = 0.0591 × 3

       Eº꜀ₑₗₗ = 0.1773 V

- So the correct answer is option (c)