Final answer:
The intermolecular forces between a hydrogen molecule and a chlorine molecule are London dispersion forces, resulting from temporary fluctuations in electron distribution within these nonpolar molecules.
Step-by-step explanation:
The question concerns the type of intermolecular forces acting between a hydrogen (H₂) molecule and a chlorine (Cl₂) molecule. Both H₂ and Cl₂ are nonpolar molecules because they consist of two identical atoms, which share electrons evenly. As a result, the predominant intermolecular force between them is the London dispersion force. London dispersion forces arise due to the temporary formation of instantaneous dipole moments, which result from short-lived fluctuations in the electron charge distribution within nonpolar molecules. The strength of these forces increases with the size of the atoms and the number of electrons.