Dispersion forces are primarily observed in which type of molecule?

Dispersion forces are primarily observed in which type of molecule?

• A. Nonpolar
• B. Polar
• C. Ions
• D. Metallic solids

Answer: (A)

Dispersion forces arise from momentary fluctuations in electron distribution that create temporary dipoles. In nonpolar molecules there are no permanent dipoles, so these temporary dipoles are the main attraction between molecules, making dispersion forces the dominant intermolecular force. In polar molecules, permanent dipoles lead to stronger dipole–dipole interactions (and potentially hydrogen bonding), so dispersion forces aren’t the primary hold-together mechanism. Ions and metallic solids are governed by entirely different bonding types—ionic bonds and metallic bonds, respectively—so dispersion forces aren’t the primary interaction there either. Hence, nonpolar molecules rely on dispersion forces as their main attractive interaction.

Dispersion forces arise from momentary fluctuations in electron distribution that create temporary dipoles. In nonpolar molecules there are no permanent dipoles, so these temporary dipoles are the main attraction between molecules, making dispersion forces the dominant intermolecular force. In polar molecules, permanent dipoles lead to stronger dipole–dipole interactions (and potentially hydrogen bonding), so dispersion forces aren’t the primary hold-together mechanism. Ions and metallic solids are governed by entirely different bonding types—ionic bonds and metallic bonds, respectively—so dispersion forces aren’t the primary interaction there either. Hence, nonpolar molecules rely on dispersion forces as their main attractive interaction.