Phase Change Process for Pure Substances Now consider phase change at constant temperature Consider pure water in a sealed container with a floating top with weights above Remove weights to reduce pressure (p) Add heat to keep constant temperature .T=20C liquid 上游通大学 March 12,2019 18 SHANGHAI JIAO TONG UNIVERSITYMarch 12, 2019 18 Phase Change Process for Pure Substances Now consider phase change at constant temperature • Consider pure water in a sealed container with a floating top with weights above • Remove weights to reduce pressure (p) • Add heat to keep constant temperature ?? 20℃