Question

The two aqueous solutions, $A$ $(AgN{O}_3)$ and $B(LiCl)$, were electrolysed using $Pt$ electrodes. The $pH$ of the resulting solutions will

• A. increase in A and decrease in B
• B. decrease in both
• C. increase in both
• D. decrease in A and increase in B

Answer 1

Answer: (D)

$AgN{O}_3$
$AgN{O}_3+H_{2}O\to Ag+H^{+}+N{O}_3^{-}+\frac{1}{2}{O}_2$
In $AgN{O}_3$ solution, $[H^{+}]$ ion increases so pH decreases.
$LiCl+H_{2}O\to L{i}^{+}+O{H}^{-}+\frac{1}{2}C{l}_2+\frac{1}{2}{H}_2$
In $LiCl$ solution, $[O{H}^{-}]$ ion increases so pH increases.