Amongst the following, the total number of compounds whose aqueous solution turns red litmus paper blue is…
Amongst the following, the total number of compounds whose aqueous solution turns red litmus paper blue is
$\begin{aligned}
&\mathrm{KCN} & \mathrm{K}_2 \mathrm{SO}_4 & \left(\mathrm{NH}_4\right)_2 \mathrm{C}_2 \mathrm{O}_4 & \mathrm{NaCl} \\
&\mathrm{Zn}\left(\mathrm{NO}_3\right)_2 & \mathrm{FeCl}_3 & \mathrm{K}_2 \mathrm{CO}_3 & \mathrm{NH}_4 \mathrm{NO}_3 \\
&\mathrm{LiCN} & & &
\end{aligned}$
Solution
The aqueous solution of $\mathrm{KCN}, \mathrm{K}_2 \mathrm{CO}_3$ and LiCN turn red litmus blue because of alkaline nature.
The anionic hydrolysis turns the solution alkaline.
Ionic equilibrium
Conceptual
III