Summary: Immiscible Liquid Phase Diagrams
  1. If a liquid is present, it exerts its own saturation pressure, independent if other immiscible liquid phases are present.     
  2. The partial pressure of a component in the vapor phase is always less than or equal to its saturation pressure.
  3. When a vapor mixture is cooled or its pressure is increased, one component will condense first unless the vapor mole fractions are proportional to their saturation pressures.
  4. For a given temperature, two liquids are in equilibrium with the vapor phase at only one pressure.
  5. For a given pressure, two liquids are in equilibrium with the vapor phase at only one temperature.