Jump to main content.

Module 4: Liquid Characteristics - Vapor Pressure - Practice Problems

Features

Instructions:: Work these problems on a sheet of paper and check your answers against those provided below.

#1

How does increasing the liquid temperature affect vapor pressure?

The vapor pressure increases.
The vapor pressure decreases.
Vapor pressure is not affected by temperature.

: Answer: a. The vapor pressure increases.; The vapor pressure of a liquid increases as the temperature of the liquid increases.

#2: If a liquid has a vapor pressure of 1 psia at 60°F and is in equilibrium with a gas at 14.7 psia absolute pressure, what is the (i) mole fraction and (ii) volume percent of the vaporized species?

: Answer: i. 0.068; Solution:

Calculate the concentration of the vaporized species as a mole fraction.

: Answer: ii. 6.8%; Solution:

Calculate the volume percent of the vaporized species.

#3: The hydrocarbon compound heptane has a vapor pressure of 0.8 psia at a temperature of 68°F in water. What is the equilibrium concentration of heptane (in ppm) in air above water? Assume that the air is at standard conditions of temperature and pressure.

Answer: 54,400 ppm heptane

Solution:

Practice Equation 3

Return To Lesson
Vapor Pressure

Next Lesson
Enthalpy

APTI Virtual Classroom

Local Navigation

Jump to main content.