CH 3 C1

For polar molecule dipole moment, depends upon geometry. Symmetrical molecule is non-polar even through it contains polar bonds. Bond dipole moment of C - H and C - Cl bond reinforce on one another.

In CHC1 3 the resultant C - H and C - Cl dipoles oppose the resultant of two C - Cl dipoles, while in CH 2 C1 2 the resultant of C - H dipoles add to resultant of two C - Cl. In case of CH 3 C1 the resultant of two C - H dipoles add to the resultant of C - H and C - Cl dipoles. Thus dipole moment of CH 3 C1 is highest among the given compounds. CC1 4 becomes symmetrical and its reduces to zero.