Consider the diagram below showing the vapor pressure curves for two solutions with equivalent concentrations. Solution A contains a nonvolatile solute while Solution B contains a volatile solute with a vapor pressure of around half of the vapor pressure of the pure solvent at a certain temperature.

Approximate the vapor-pressure curve for the pure solvent and determine its normal boiling point.

• A. BP = 50°C
• B. BP = 60°C
• C. BP = 55°C
• D. BP = 65°C

Answer: (B)