During the electrolysis of molten sodium chloride, the time required to produce $0.10$ mol of chlorine gas using a current of $3$ amperes is

Solution & Explanation

\textbf{Answer:} (B) 110 minutes \textbf{Solution:} At the anode chlorine is liberated: $2\mathrm{Cl}{}^{-}\to \mathrm{Cl}{}_2+2\mathrm{e}{}^{-}$. Thus $1$ mol of $\mathrm{Cl}{}_2$ requires $2F$ of charge, so $0.10$ mol requires $$Q=0.10\times 2\times 96500=19300\text{C}.$$ From $Q=It$, $$t=\frac{Q}{I}=\frac{19300}{3}\approx 6433\text{s}\approx 110\text{minutes}.$$