Question

Which of the following is a strong electrolyte ?

• A. $Ca(N{O}_3{)}_2$
• B. $HCN$
• C. $H_{2}S{O}_3$
• D. $N{H}_{4}OH$

Answer 1

Answer: (A)

$Ca(N{O}_3{)}_2$

$Ca{\left({NO}_3\right)}_2⟶{Ca}^{2+}+{2NO}_3^{-}$ because its $Ka$ is very very high

Less $Ka$

$HCN\rightleftharpoons H^{+}+{CN}^{-}$ (weak acid)

$H_2{CO}_3\rightleftharpoons H^{+}+{HSO}_3^{-}$ (weak acid)

${NH}_{4}OH\rightleftharpoons {NH}_4^{+}+{OH}^{-}$ (weak acid)