Question

Na metal cannot be obtained by electrolysis of aqueous NaCl solution. Explain why.

Answer 1

When aqueous $NaCl$ solution is electrolysed, $C{l}_2$ is formed at the anode and $Na$ at the cathode. But $Na$ is very reactive with $H_{2}O$ forming $NaOH$ and $H_2$. Thus, Na cannot be prepared by electrolysis of aq. $NaCl.$

$NaCl\left(aq\right)\rightleftharpoons N{a}^{+}+C{l}^{-}$

At anode: $2C{l}^{-}\to C{l}_2+2e^{-}$

At cathode: $2N{a}^{+}+2e^{-}\to 2Na$

$2Na+2H_{2}O\to 2NaOH+H_2$