Question

NH3 is more polar than NF3

Answer 1

Dipole moment of NH3 is higher than NF3 molecule.Both the molecules have pyramidal shape with a lone pair of electrons on nitrogen atom. There is a greater difference in electronegativity between nitrogen and hydrogen thanthere is between nitrogen and fluorine. the bond dipoles oppose the effect of the lone pair.

Answer 2

It is  more polar due to the band movements.

• With a lone pair of electrons on the nitrogen atom, the two molecules retain a pyramidal form.
• The differential in electro negativity among nitrogen and hydrogen is higher than the amount across nitrogen and fluorine.
• The activity of the lone pair is counteracted by the bond dipoles. In NH3, the outcome of three H-N bond transitions and a single electron pair moment works in a similar way.
• In NF3, however, the product of three N-F bond transitions and the lone electron pair moment has the opposite effect.
• As a result, NH3 has a higher polarity than NF3.