Question

WHY NH3 HAS HIGHER DIPOLE MOMENT THAN NF3 ??????????????

Answer 1

In NH3, N is more electronegative than H. So, N pulls the electrons from H towards itself and so, the direction ofmoment due to the N-H bonds is in the same direction as that of the lone pair of electrons on Nitrogen. ... And, so we have NH3 whose dipole moment is much higher than that of NF3.

Answer 2

The reason behind this is..
In NH3.
the electron density shifted more towards Nitrogen atom because of its high electronegativty..

but in NF3

the electron quality distrusted to fluorine atoms as it has more electronegative than nitrogen..