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Raoult's Law and Vapor-Liquid Equilibrium: Interactive Simulations

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.

Simulation: Visualization of Vapor-Liquid Equilibrium in a Binary Mixture

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 relative volatility of 2.0 (blue/green), and a liquid mole fraction of 0.50, when the liquid mole fraction increases for blue molecules, does the vapor mole fraction of blue molecules increase or decrease?
  2. For a relative volatility of 2.0, and a liquid mole fraction of 0.50, when the relative volatility (blue/green) increases , does the vapor mole fraction of blue molecules increase or decrease?
Simulation: P-x-y and T-x-y Diagrams for VLE

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

  1. When the temperature increases, what happens to the two curves in the P-x-y diagram? Do they move to higher or lower pressure or do they not change? Why?
  2. If the black dot moves at constant overall composition to higher pressure at constant temperature in the P-x-y diagram, do the mole fractions of the liquid and vapor phases increase or decrease or does one increase and one decrease?
  3. How is the T-x-y diagram different from the P-x-y diagram?