What type of intermolecular force is present in nonpolar molecules?

Nonpolar molecules exhibit London dispersion forces as their primary type of intermolecular force. These forces arise due to temporary fluctuations in electron distribution within molecules, which can create instantaneous dipoles. As a result, even in nonpolar molecules, the uneven distribution of electrons can induce a dipole in neighboring molecules, leading to a weak attraction between them.

These London dispersion forces are present in all molecular substances, but they are particularly significant in nonpolar molecules because this is the only type of intermolecular interaction available to them, as they lack permanent dipoles that would lead to dipole-dipole interactions or hydrogen bonding. In contrast, dipole-dipole interactions occur between polar molecules, while hydrogen bonding is a specific, stronger form of dipole-dipole interaction that involves hydrogen and highly electronegative elements like oxygen or nitrogen. Ion-dipole interactions occur in mixtures of ionic compounds and polar solvents, which also does not apply to nonpolar molecules. Thus, London dispersion forces correctly represent the intermolecular forces present in nonpolar molecules.