Dipole Moments, Polar Molecules, Valence Bond Theory

Dipole Moments and Polar Molecules

---------------------->

Dipole moment = the product of the charge, Q, and the distance, r, between the charges:  Table 10.3 lists the dipole moments of several molecules.

Diatomic molecules containing atoms of different elements have dipole moments and are called polar molecules.  Examples include: HCl, CO, and NO.

Diatomic molecules containing atoms of the same element are examples of non-polar molecules because they do not have dipole moments.  For example: H2, O2, and F2.

For a molecule made up of three or more atoms both the polarity of the bonds and the molecular geometry determine whether there is a dipole moment.  Example is CO2 which can be either linear or bent.