Which of the following properties indicates the presence of weak intermolecular forces in a liquid?

• A. High viscosity
• B. Low vapor pressure
• C. High surface tension
• D. Low boiling point

Answer: (D)

Verified step by step guidance

1. Understand that intermolecular forces (IMFs) are the forces of attraction between molecules in a liquid, and their strength affects physical properties such as boiling point, vapor pressure, viscosity, and surface tension.
2. Recall that strong intermolecular forces result in higher boiling points because more energy is required to separate the molecules from the liquid phase to the gas phase.
3. Recognize that weak intermolecular forces lead to a low boiling point, because less energy is needed to overcome these forces and convert the liquid into vapor.
4. Analyze other properties: high viscosity and high surface tension usually indicate strong intermolecular forces, while low vapor pressure also suggests strong IMFs because fewer molecules escape into the vapor phase.
5. Conclude that among the given options, a low boiling point is the property that best indicates the presence of weak intermolecular forces in a liquid.