This module uses a screencast and an interactive simulation to explain how to use an equation of state or steam tables to calculate the departure function. 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, question in the screencast, and questions to answer before using the interactive simulation, 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 screencast that explains the enthalpy departure function.
3. Review important equations for departure functions.
4. Use the interactive simulation to compare real and ideal gas enthalpies and entropies.
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.