Question

The molecule having the smallest bond angle is___?

• A. ${\mathrm{PCl}}_3$
• B. ${\mathrm{AsCl}}_3$
• C. ${\mathrm{NCl}}_3$
• D. ${\mathrm{SbCl}}_3$

Answer 1

The correct option is D

${\mathrm{SbCl}}_3$

Explanation for correct option

(D)${\mathrm{SbCl}}_3$

Bond angle

• It is defined as the angle between the orbitals containing bonding electron pairs around the central atom in a molecule or complex ion.
• The bond angle is measured in degrees.
• It can be obtained experimentally using spectroscopic methods.
• The bond angle is directly proportional to the electronegativity of the central atom.

Order of bond angle

• On going down the group from nitrogen to antimony, electronegativity decreases. So, the bond order also decreases.
• The order of bond angle is as follows:-

${\mathrm{NCl}}_3>{\mathrm{PCl}}_3>{\mathrm{AsCl}}_3>{\mathrm{SbCl}}_3$

• So, ${\mathrm{SbCl}}_3$ (Antimony trichloride) has the smallest bond angle.

Explanation for incorrect options

The molecule having the smallest bond angle is ${\mathrm{SbCl}}_3$. Hence, options (A),(B), (C) are incorrect.

Hence option (D) is correct. The molecule having the smallest bond angle is ${\mathrm{SbCl}}_3$.