Which of the following molecules has the maximum dipole moment ?
CO2
CH4
NH3
NF3
As we learnt in
Resultant dipole moment -
Let XY and XZ are two polar bonds inclined at an angle their dipole moments are
- wherein
Zero dipole moment -
A molecule having two or more polar bonds may have zero net when the molecule has regular structure
- wherein
Example:-
In NH3, H is less electronegative than N and hence dipole moment of each N—H bond is towards N and create high net dipole moment, where as in NF3, F is more electronegative than N, the dipole moment of each N—F bond is opposite to that of lone pair hence reducing the net dipole moment.
Option 1)
CO2
This option is incorrect
Option 2)
CH4
This option is incorrect
Option 3)
NH3
This option is correct
Option 4)
NF3
This option is incorrect