Which type of intermolecular force is primarily responsible for the interactions between O_2 molecules in the liquid or solid state?

• A. Dipole-dipole interactions
• B. London dispersion forces
• C. Ion-dipole forces
• D. Hydrogen bonding

Answer: (B)

Verified step by step guidance

1. Identify the molecular structure and polarity of O_2. Since O_2 is a diatomic molecule composed of two identical oxygen atoms, it is nonpolar and does not have a permanent dipole moment.
2. Recall that dipole-dipole interactions occur between molecules with permanent dipoles, which O_2 lacks, so these forces are not significant here.
3. Understand that hydrogen bonding requires a hydrogen atom bonded to highly electronegative atoms like N, O, or F, which is not present in O_2 molecules.
4. Recognize that ion-dipole forces involve interactions between ions and polar molecules, which is not applicable to neutral O_2 molecules.
5. Conclude that the primary intermolecular force between O_2 molecules is London dispersion forces, which arise from temporary fluctuations in electron distribution creating instantaneous dipoles even in nonpolar molecules.