Which statement best describes the relationship between intermolecular forces and vapor pressure in a liquid?

• A. Stronger intermolecular forces result in higher vapor pressure.
• B. Weaker intermolecular forces result in lower vapor pressure.
• C. Stronger intermolecular forces result in lower vapor pressure.
• D. Intermolecular forces do not affect vapor pressure.

Answer: (C)

Verified step by step guidance

1. Understand that vapor pressure is the pressure exerted by a vapor in equilibrium with its liquid at a given temperature.
2. Recognize that intermolecular forces are the attractions between molecules in a liquid, such as hydrogen bonding, dipole-dipole interactions, and London dispersion forces.
3. Know that stronger intermolecular forces mean molecules are held more tightly in the liquid phase, making it harder for them to escape into the vapor phase.
4. Therefore, stronger intermolecular forces lead to fewer molecules escaping the liquid, resulting in a lower vapor pressure.
5. Conversely, weaker intermolecular forces allow more molecules to escape, increasing the vapor pressure.