Fugacities of Mixtures: Interactive Simulations
These simulations were prepared using MathematicaDownload the free CDF player, and then download the simulation CDF file (click on the title or the figure to download below). Try to predict the behavior when a parameter changes before using a slider to change that parameter. Screencasts are provided that explain how to use these simulations.
 

Simulation: Fugacities in an Ideal Binary Mixture

This Demonstration shows how the fugacities of benzene(B) and toluene(T) change with temperature and molar composition at constant pressure. Use the sliders to vary the temperature and overall mole fraction of benzene. Use the buttons to view the temperature-composition diagram (T-x-y), the fugacity-temperature plot, or both plots at once.

 


Try to answer these questions before determining the solution with the simulation:

  1. Starting with an ideal liquid mixture, as temperature increases at constant pressure, how do the fugacities of each component change? 
  2. When an ideal binary liquid mixture is heated at constant pressure to its bubble point and vapor starts to form, how do the fugacities of each component change as more vapor forms?
  3. Starting with an ideal gas mixture at constant pressure, how do the fugacities of each component change as the temperature increases?
       
      



Simulation: Fugacities in a Can of Soda

The fugacities of water and carbon dioxide are calculated as a function of temperature for a closed container, which is a model of a can of soda. The concentrations of the two components are calculated in both the liquid and the gas phases. Change the temperature inside the can with a slider. 


Try to answer these questions before determining the solution in the simulation:

  1. As the temperature increases for the can of soda, what happens to the pressure?
  2. As the temperature increases for the can of soda, how do the fugacities of H2O and CO2 change?
  3. For a can of soda at 0°C, is the CO2 or the H2O fugacity higher in the liquid phase? How do you know this?