Question

The cell potential for the following cell notation is approximately:

M(s) | M³⁺ (aq, 0.01 M) || N²⁺ (aq, 0.1 M) | N(s)

`E_(M^(3+)//M)^0` = 0.6 V and `E_(N^(2+)//N)^0` = 0.1 V

Options

• 0.51 V

• 1.5 V

• 2.0 V

• 2.5 V

Answer 1

0.51 V

Explanation:

\[\ce{(M -> M^3+ + 3e) × 2; (N^2+ + 2e -> N) × 3}\]

Overall reaction: \[\ce{2M_{(s)} + 3N^{2+}_{ (aq)} -> 2M^{3+}_{ (aq)} + 3N_{(s)}}\]

∴ `E_(cell) = E_(cell)^\circ - 0.059/6 log  ([M^(3+)]^2)/([N^(2+)]^3)`

= `-0.6 + 0.1 - 0.059/6 log  (10^-2)^2/(10^-1)^3`

= `-0.5 - 0.059/6 log 10^-1`

= 0.51 V