P-x-y and T-x-y Diagrams for VLE

The vapor-liquid equilibrium (VLE) behavior of a benzene (C6H6)/toluene (C7H8) mixture is demonstrated in P-x-y and T-x-y diagrams. The blue line represents the liquid-phase boundary (bubble point) and the green line represents the vapor-phase boundary line (dew point). Drag the black dot on either diagram and the bar chart shows the amounts of liquid (blue) and vapor (green); the system contains a total of 1 mol. The mole fractions of benzene in each phase (xB for liquid phase, yB for vapor phase) are also shown in the bar graph. Use sliders to vary the temperature for the P-x-y diagram and the pressure for the T-x-y diagram. This system is modeled by Raoult’s law because a benzene/toluene liquid phase is expected to be ideal.

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This simulation was made at the University of Colorado Boulder, Department of Chemical and Biological Engineering.  Authors: Rachael L. Baumann, Neil Hendren

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