Van der Waals forces are

• A. They are the strongest type of covalent bond.
• B. They are the two weakest intermolecular attractions—dispersion and dipole forces.
• C. They are ionic bonds formed between oppositely charged ions.
• D. They involve sharing electrons equally in a covalent bond.

Answer: (B)

Van der Waals forces are the intermolecular attractions that hold molecules together in liquids and solids. They are generally the weakest type of intermolecular force, weaker than the bonds that hold atoms together within a molecule. They arise from two main effects: London dispersion forces, caused by temporary fluctuations in electron distribution producing instantaneous dipoles, and dipole-dipole interactions between polar molecules with permanent dipoles. This makes them the two weakest kinds of intermolecular attraction in many introductory descriptions.

They are not the strongest covalent bonds, which involve sharing electrons within a molecule. They are not ionic bonds formed between oppositely charged ions, and they do not involve sharing electrons equally in a covalent bond.