The electronegaivity difference between `N` and `F` is greater than that between ` N` and `H` yet the dipole moment of `NH_2` ( 1 .5 D) is larger than that of ` NF_3 ( 0. 2 D)`. This is because :

Options

A. In `NH_(3)` the atomic dipole and bond dipole are in the same direction , wheras in `NF_(3)` these are in opposite directions
B. In `HN_(3)` as well as `NF_(3)` the atomic dipole and bond dipole are in opposite directions
C. In `HN_(3)` the atomic dipole and bond dipole are in the opposite direction , wheras in `NF_(3)` these are in the same direction
D. In `NH_(3)` as well as `NF_(3)` the atomic dipole and bond dipole are in same direction

Answer

a

Explanation

In `NH_(3)` the atomic dipole and bond dipole are in the same direction, wheras in `NF_(3)` these are in opposite direction so in the former case they are added up whereas in the latter case net result is the reduction of dipole moment it has been shown in the following figure.