Question

Correct order of dipole moment is ______

• A.
• B.
• C.
• D.

Answer 1

The correct option is D

In $B{F}_3$, there are no lone pairs on Boron.

[from VSEPR Theory] [ep = $\frac{3+3}{2}=3\&3$ ligands (F)]

Thus, net dipole moment in $B{F}_3$ is zero of symmetrical trigonal planar shape.

Since F is more electronegative than N,

The lone pair moment opposing the bond pair moment.

Since N is more electronegative than H,

The lone pair moment is in the direction of bond pair moment.

Thus, the order will be $B{F}_3<N{F}_3<N{H}_3$