Question

The bond-angle in $As{H}_3$ is greater than that in:

• A. $N{H}_3$
• B. $H_{2}O$
• C. $BC{l}_3$
• D. none of these

Answer 1

Answer: (D)

$BC{l}_3$ has bond-angle equal to $120^{\circ }$ (trigonal planar). $N{H}_3$ and $H_{2}O$ have $s{p}^3$ hybridisation but due to the presence of lone pair of electrons, they have bond angle less than $109^{\circ }28\cdot \left(N{H}_3-107^{\circ },H_{2}O-104.5^{\circ }\right)\cdot As{H}_3(s{p}^3$ hybrid) has smaller bond angle than $NHs$ due to less electronegativity of As than $N$.