Interactive Self-Study Module: Mixing and Solution
Overview:
This module uses screencasts and interactive simulations to explain the change in energy associated with mixing liquids, and the relationship between heat of mixing and deviations from Raoult’s law. 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:
- Attempt to answer the multiple choice ConcepTest and solve the example problem before watching the screencasts or working with the simulations.
- Watch the screencasts that describes enthalpy changes when liquids mix and answer the questions within the screencast.
- Review the important equations for mixing and solutions.
- Use the interactive simulation to further understand the behavior of energy changes when forming nonideal solutions.
- Use the quiz-yourself interactive simulation to test your understanding by identifying pure component and mixture enthalpies or entropies in a binary solution.
- Try to solve the example problems before watching the solutions in the screencast.
- Answer the ConcepTests.
- Look at the list of key points, but only after you try to list the key points yourself
Motivation:
- For nonideal mixtures, the enthalpy change on mixing can be positive or negative. Such mixtures exhibit vapor-liquid equilibrium behavior that deviates from Raoult’s law.
- This module is intended for thermodynamics and material and energy balances courses.
Before studying this module, you should:
- be able to apply the First Law – Closed Systems
After studying this module, you should be able to:
- Calculate the heat of mixing from an enthalpy versus mole fraction diagram when two pure components are mixed.
- Calculate the adiabatic temperature from an enthalpy versus mole fraction diagram when two pure components are mixed.
- Calculate the adiabatic temperature from an enthalpy-mole fraction diagram when two mixtures of different mole fractions (but containing the same two components) are mixed.
- Determine from an enthalpy-mole fraction diagram whether mixing of two pure components is endothermic, exothermic, or ideal.
- Predict positive or negative deviations from Raoult’s law from the heat of mixing.