Vapor-Liquid Equilibrium Diagram for Non-Ideal Mixture
This Demonstration presents and diagrams for vapor-liquid equilibrium (VLE) of a benzene/ethanol mixture. Click and drag the black dot to change the benzene mole fraction and the temperature or pressure. This liquid mixture is non-ideal and the system has an azeotrope (constant-boiling mixture) at the conditions used. The activity coefficients in the modified Raoult's law are calculated using the two-parameter Margules model. The bar chart on the right displays the relative amounts of liquid (blue) and vapor (green) in equilibrium and the mole fraction of benzene in each phase ( for liquid phase, for vapor phase); the relative amounts are calculated using the lever rule. The blue line represents the liquid-phase boundary (bubble point), and the green line represents the vapor-phase boundary (dew point).