The x-y diagram (vapor mole fraction versus liquid mole fraction) for vapor-liquid equilibrium (VLE) is shown for a methanol/water mixture being fed to a flash drum. The corresponding T-x-y diagram shows how the points on the x-y diagram are obtained; each point corresponds to a different temperature. Use buttons to view the x-y and T-x-y diagrams separately or to view both simultaneously. Use the “liquid/vapor ratio” slider to select the ratio leaving the flash drum; use the other slider to select the feed composition to the flash separation.