A current of $2.00 A$ is passed through aqueous $ZnSO X_{4}$ for $1930 s$ and $1.14 g$ of zinc is deposited at the cathode. Find the current efficiency in percent (nearest integer). Take Zn = 65, $F = 96500 C mo l^{- 1}$ .

Numerical answer type, answer in %, tolerance 1.

Answer: 88 %

Charge

Q = 2.00 \times 1930 = 3860 C = 0.0400 mol

of electrons. Theoretical zinc (

Zn X^{2 +} + 2 e X^{-} Zn

)

= 0.0200 \times 65 = 1.30 g

. Current efficiency

= \frac{1.14}{1.30} \times 100 = 87.7% \approx 88%

. The rest of the charge is lost mainly to hydrogen evolution.