Immiscible Liquids Phase Diagrams: Interactive Simulations

These simulations were prepared using Mathematica. Download the free Wolfram player, and then download the simulation CDF file (link given below or click on figure to download). Try to predict the behavior when a parameter changes before using a slider to change that parameter. Screencasts below explain how to use these simulations.

This simulation shows a pressure-composition phase diagram for two immiscible liquids, benzene and water. The temperature and the overall benzene mole fraction can be changed with a slider. A bar graph shows the moles of liquid water (blue), liquid benzene (orange), and vapor (green). Changing the piston height changes the amounts in each phase. Selecting “piston-cylinder” instead of “amounts of each phase” shows the volume of each phase on a log scale.

Try to answer these questions before determining the answer with the simulation. We suggest that you write down the reasons for your answers.

  1. For a temperature of 122°C, how many phases are present for a benzene mole fraction 0.30 and a pressure of 3.8 bar?
  2. How does the pressure-composition graph change as the temperature increases?

This simulation shows a temperature-composition phase diagram for two immiscible liquids, benzene and water. The pressure and overall mole composition can be changed with sliders.The bar graph shows the moles of liquid water (blue), liquid benzene (orange), and vapor (green). The system contains one mole total.

Try to answer these questions before determining the answer with the simulation. We suggest that you write down the reasons for your answers.

  1. How many phases are present at 12 bar and 160°C for a benzene mole fraction of 0.35?
  2. How does the graph change as pressure increases?