The drift of bonded electrons towards the more electronegative element results in a dipole.The overall dipole depends on the shape of the molecule. Individual dipoles can either cancel each other out or reinforce each other.If there is an overall dipole, the molecule is said to be polar. The polarity of a dipole is measured by its dipole moment, which is the size of the partial charge (δ) multiplied by the distance of separation between the charges.