In this simulation, liquid propane is injected into an evacuated 2-L spherical tank that is held at constant temperature. Depending on the number of moles injected and the temperature (control both with sliders), the propane either vaporizes completely or forms two phases in vapor-liquid equilibrium (VLE). When propane is in VLE, the tank pressure equals the saturation vapor pressure of propane; otherwise, the pressure is calculated using the ideal gas law. The pressure is displayed at the top of the tank. Click the inject button to inject liquid into the tank. The intensity of the blue color of the vapor is proportional to the vapor density. The volume of the liquid in the tank exaggerated relative to the vapor volume for better visualization. The bar graph to the right shows the number of moles of liquid and vapor in the tank.