Which of the following factors affects the vapor pressure of a liquid?

• A. Color of the liquid
• B. Volume of the container
• C. Strength of intermolecular forces
• D. Molar mass of the liquid

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 vapor pressure depends on how easily molecules escape from the liquid phase into the vapor phase, which is influenced by the strength of intermolecular forces.
3. Recall that stronger intermolecular forces mean molecules are held more tightly, resulting in lower vapor pressure, while weaker forces allow more molecules to escape, increasing vapor pressure.
4. Note that factors like the color of the liquid or the volume of the container do not affect the vapor pressure because they do not change the energy required for molecules to vaporize.
5. Understand that molar mass alone does not directly determine vapor pressure; it is the intermolecular forces associated with the molecules that primarily affect vapor pressure.