Which of the following phase changes involves an increase in the attractive force between molecules?

• A. Condensation
• B. Vaporization
• C. Melting
• D. Sublimation

Answer: (A)

Verified step by step guidance

1. Understand that phase changes involve changes in the physical state of a substance, and these changes are accompanied by changes in the intermolecular forces between molecules.
2. Recall that when a substance changes from a phase with weaker intermolecular forces to a phase with stronger intermolecular forces, the attractive forces between molecules increase.
3. Analyze each phase change: Vaporization and sublimation involve going from liquid or solid to gas, which means molecules move apart and intermolecular forces decrease.
4. Melting involves going from solid to liquid, where molecules become less ordered and intermolecular forces generally decrease.
5. Condensation involves going from gas to liquid, where molecules come closer together and the attractive forces between molecules increase.