Question

Which of the following statements is/are true regarding $N{H}_4^{+}$?

• A. $N{H}_4^{+}$ contains a dative bond
• B. Bond angle increases when a bond is formed between $N{H}_3$ and $H^{+}$.
• C. $N{H}_4^{+}$ has pyramidal shape.
• D. The type of hybridisation changes when a bond is formed between $N{H}_3$ and $H^{+}$

Answer 1

Answer: (A), (B)

The correct options are
A $N{H}_4^{+}$ contains a dative bond
B Bond angle increases when a bond is formed between $N{H}_3$ and $H^{+}$.

(A) $N{H}_4^{+}$ ion contains a dative bond (co-ordinate covalent bond) between $N$ atom and $H$ atom.
$H_{3}N\to H^{+}$
(B) Bond angle increases when a bond is formed between $N{H}_3$ and $H^{+}$. In $N{H}_3$ molecule, due to repulsion between lone pair and bond pair of electrons, the bond angle decreases. When $N{H}_4^{+}$ ion is formed, lone pair is converted into bond pair. The inter electron repulsion decreases and bond angle increases.
(C) $N{H}_4^{+}$ ion has tetrahedral shape. $N{H}_3$ molecule has pyramidal shape.
(D) The type of hybridisation is not changed when bond is formed between $N{H}_3$ and $H^{+}$