A bond dipole looks at the charge distribution between two bonded atoms while a molecular dipole moment looks at the charge distribution of the entire molecule.
Work Step by Step
Bond dipoles look at individual bonds, so if two bonded things have differing electronegativities, they have a bond dipole. Contrarily, molecular dipoles consider how polar an entire molecule is. Unlike bond dipoles, it is possible to have no molecular dipole even when there are polar bonds. This occurs when the bond dipoles cancel each other out, leading to a molecule with no net dipole.