How long will it take to produce 1 kg of Cl₂ from 20 Lit of 20% by weight NaCl aqueous solution by passing 25 A current with 62% current efficiency is passed.

$1\mathrm{kg}{\mathrm{Cl}}_2=\frac{1000}{35.5} \mathrm{equivalentof} {\mathrm{Cl}}_2=28.17 \mathrm{equivalentof} {\mathrm{Cl}}_2$
Theoretical electricity required - 28.17 F
Efficiency is 62%
Electricity required (experimental) $=\frac{28.17\times 100\mathrm{F}}{62}=45.44\mathrm{F}$
$\Rightarrow 45.44\times 96500=25\mathrm{t};\mathrm{t}=48.72\mathrm{hr}$