Question

Which among the following is least polar *

a NH3
b NF3
c CH4
d HCl

Answer 1

Answer:

According to me, answer is CH4

Answer 2

The least polar among the following is:

(c) CH4

- NH3 has a lone pair and the direction of all the dipole moment of polar bonds is towards the N atom. It has a resultant dipole moment of 1.46 D.

- NF3 also has a lone pair but all the direction of all the dipole moments of polar bonds is towards away from the N atom. So, it has a low resultant dipole moment of 0.24 D.

- CH4 is a non-polar molecule and tetrahedral in shape. All of its polar bonds cancel out their dipole moments. The resultant dipole moment is Zero (0).

- HCl is a polar molecule with dipole moment 1.03 D.