Which compound has a larger dipole moment:.
CH3Cl
or
CH2Cl2?

Explanation:

In this case, we must analyze the structure for each molecule. In the case of , we have a bond with a chlorine atom. Chlorine has a high electronegativity, therefore the C-Cl bond has a relatively large dipole moment since we have a high electronegativity difference.

In the molecule, we have two bonds of this type, therefore we will have two high dipole moments. Thus, the net dipole moment for this second molecule should be higher.

This statement can be confirmed if we look at the dielectric constant, this value is an indicator of the polarity of a molecule. If we have a high dielectric constant there will be more polarity and therefore a higher net dipole moment.

See figure 1 to further explanations

I hope it helps!