Question

Which one of the following can be classified as a Bronsted base:

• A. $N{O}_3^{-}$
• B. $H_3{O}^{+}$
• C. $N{H}_4^{+}$
• D. $HCl$

Answer 1

The correct option is A $N{O}_3^{-}$

Those compound which accept $H^{+}$ is called Bronsted base and which donate $H^{+}$ is called Bronsted acid.

• $N{O}_3^{-}+H^{+}\rightleftharpoons HN{O}_3$ . Here, $N{O}_3^{-}$​ accept $H^{+}$ and form $HN{O}_3$​. So it is a Bronsted base. Option (a) is correct.
• $H_3{O}^{+}\rightleftharpoons H_{2}O+H^{+}$ . So it can donate $H^{+}$ and it called Bronsted acid. Option (b) is incorrect.
• $N{H}_4^{+}\rightleftharpoons N{H}_3+H^{+}$ . So it also donate $H^{+}$ and it called Bronsted acid.Option (c) is incorrect.
• $HCl\rightleftharpoons C{l}^{-}+H^{+}$. $HCl$ is a Bronsted acid which dissociates to give $H^{+}$. Therefore option (d) is incorrect.