Question

For a cell reaction in involving a two electron change, the Stanford emf of the cell is found to be 0.295 V at 25°C. The equilibrium constant of the reaction at 25°C will be:

Options

• 1 × 10⁻¹⁰

• 29.5 × 10⁻²

• 10

• 1 × 10¹⁰

Answer 1

1 × 10¹⁰

Explanation:

Using the relation,

`E_(cell)^circ = (2.303  RT)/(nF)  log K_c`

= `0.0591/n  log K_c`

∴ 0.295 V = `0.0591/2  log K_c`

or log K_c = `(2 xx 0.295)/0.0591`

K_c = 1 × 10¹⁰