Both NH3 and NF3 have same structures but dipole moment is different. Why?
Answers
It is because in NH3, the dipole moment is only towards the up because N is more electronegative than H and also dipole moment is in the direction of the lone pair electrons, which are present above the N atom, so the net dipole is towards the upper side. But in NF3, the dipole moment is not directed towards either side because dipole moment due to F, is downwards and due to lone pair, the dipole moment is towards up.
So, the dipole moment of NH3 is more than NF3.
❤.In NH3, the directionof the orbital dipole moment due to lone pair is in the same direction of the 'resultant dipolemoment' of the 3N-H bonds.
❤.Hence,the net dipole moment of NH3 is positive.
❤. But in NF3, molecule the direction of the orbital dipole moment due to lone pair is in the opposite direction to the 'resultant dipole moment'of the 3 N-F bonds.
❤.Hence, its net dipole moment decreases.
❤. Therefore,dipole moment of NH3 is greater than that of NF3
