Solution:
The molecules having distorted geometry have dipole moment and those having regular geometry have zero dipole moment. \(\because \mathrm{NH}_{3}, \mathrm{CH}_{3} \mathrm{Cl}\) and \(\mathrm{ClO}_{2}\) have distorted geometry.. \(\therefore\) They have dipole moment. \(\because B F_{3}\) has regular triangular planar geometry and thus, the dipole moment of \(B F_{3}\) is zero.
