4C  CHANGE OF STATE

4C10  PVT Surfaces
4C20  Phase Changes
            .20 Ice Bomb
            .30 Regelation
            .45 CO₂ Expansion Cooling
4C30  Phase Changes: Liquid-Gas
            .10 Boil Water Under Reduced Pressure
            .30 Helium and CO₂ Balloons in Liquid Nitrogen
            .35 Liquid Nitrogen in Balloon
4C31  Cooling by Evaporation
            .10 Cryophorus
            .20 Freezing by Boiling
            .30 Drinking Bird
4C32  Dew Point and Humidity
4C33  Vapor Pressure
4C40  Sublimation
            .10 Sublimation of CO₂
4C45  Phase Changes: Solid-Solid
4C50  Critical Point
            .10 CO₂ Critical Point