Interactive Self-Study Module: Osmosis and Reverse Osmosis


This module uses screencasts and interactive simulations to explain osmosis and reverse osmosis. It then provides example problems to allow the user to test themselves. Your retention of material in this module will increase if you write down reasons for your answers to ConcepTests, questions in screencasts, and questions to answer before using interactive simulations, and you try to solve the example problems before watching the screencast solutions. We suggest using the learning resources in the following order:

  1. Attempt to answer the multiple-choice ConcepTest and solve the example problem before watching the screencasts or working with the simulations.
  2. Watch the screencasts that describe osmosis and reverse osmosis and answer the questions within the screencasts.
  3. Review important equations for osmosis and reverse osmosis.
  4. Use the interactive simulations to further understand osmosis and reverse osmosis.
  5. Try to solve the example problems before watching the solutions in the screencasts.
  6. Answer the ConcepTests.
  7. Look at the list of key points, but only after you try to list the key points yourself.
  • Osmotic pressure is important in biological processes. The molecular weight of a solute can be determined by measuring osmotic pressure. Reverse osmosis is used for purifying water in desalination plants.
  • This module is intended for a thermodynamics or separations course. 
Before studying this module, you should be able to:
After studying this module, you should be able to:
  • Calculate the osmotic pressure for a liquid mixture.

  • Calculate molecular weight of a solute given the osmotic pressure of the solute

  • Explain how fugacity can be used to calculate the equation for osmotic pressure.

  • Explain how reverse osmosis works to purify a mixture.

  • Understand how concentration polarization affects permeation through a membrane.