2.3 Boiling-point Elevation and Freezing-point Depression 2.3.1 Boiling-point Elevation 2.3.1.1 Normal boiling point The normal boiling point of a liquid is the temperature at which its vapor pressure equals 101.3 kPa(I atm)2.3 Boiling-point Elevation and Freezing-point Depression 2.3.1 Boiling-point Elevation 2.3.1.1 Normal boiling point The normal boiling point of a liquid is the temperature at which its vapor pressure equals 101.3 kPa(1 atm)