What is the difference of dipole moment of NH3 and NF3 respectively?

 Both NH3 and NF3 have sp3 hybridization and trigonal pyramidal shape.

Fluorine has more electronegative than nitrogen but NH₃ has more dipole moment than NF₃.  In NH3, Nitrogen is more electronegative than Hydrogen. So Nitrogen pulls the electrons from Hydrogen towards itself and so, the direction of moment due to the N-H bonds is in the same direction as that of the lone pair of electrons on Nitrogen. Hence here additive effect appears while in case of NF₃, Fluorine is more electronegative than Nitrogen. So fluorine pulls electrons from nitrogen towards itself  so that direction of moment due to N-F bonds is in the opposite direction as the lone pair of electron on nitrogen atom. Hence it is clear dipole moment of NH₃ is more than NF₃.

Related Questions:

(1) The Dipole moment of Chloromethane is more than Fluoromethane. Explain.

(2) CO2 has got dipole moment of zero why?

(3) Dipole moment of CCl4 is zero while that of CHCl3 is non zero. explain.

(4) Compare the dipole moment of H2O and F2O.

(5) Which has more dipole moment of NH3 or NF3?

(6) Which NH3 and NF3 have the highest dipole moment and why?

(7) Why dipole moment of NH3 is lower than NH3?