Direction of dipole moment expected for hydrogen bromide

Question

Illustrate the direction of the dipole moment expected for hydrogen bromide?

Answer 1

An HBr molecule is linear (clearly, as it comprises two atoms only). The dipole moment is a vector, parallel to a bond, pointing to the partially positively charged atom, i.e., in this situation, hydrogen. Magnitude of the dipole moment is difference in the fractional electrical charges on every atom times the spatial separation of atoms in that bond. In a molecule with more than one bond (more than two atoms), the dipole moment of all bond must be added vectorially and the resulting vector will determine dipole moment of that molecule. For example, carbon dioxide contains two carbon-oxygen double bonds of high polarity, but because molecule is linear, and individual dipoles oppose each other, carbon dioxide molecule has no left dipole moment.