Question

$H_2$ gas is liberated at cathode and anode both by electrolysis of the following solution except in:

• A. $NaCl$
• B. $NaH$
• C. $LiH$
• D. $HCOONa$

Answer 1

The correct option is A $NaCl$

In Nelson's cell, $H_2$ gas is liberated at cathode wheres $C{l}_2$ gas is liberated at the anode, on electrolysis of solution of $NaCl$.

$NaCl\rightleftharpoons N{a}^{+}+C{l}^{-}$
$H_{2}O\rightleftharpoons H^{+}+O{H}^{-}$

At cathode,
$H^{+}+e^{-}\to H$

$H+H\to H_2\uparrow$

At anode,
$C{l}^{-}\to Cl+e^{-}$

$Cl+Cl\to C{l}_2\uparrow$