H₂O-CH₃CH₂OH equilibrium phase diagram. Phases at equilibrium for the system H₂O-CH₃CH₂OH are shown as a function of chemical composition (weight percent H₂O-CH₃CH₂OH) and temperature. The blue area indicates temperatures and compositions for which a single liquid phase ("vodka") is present at equilibrium. Areas that have the horizontal line pattern indicate temperatures and compositions for which two phases are in equilibrium. The liquid region is bounded on the lower right by an ethanol-saturation curve and on the left by an ice-saturation curve. Lowering of the temperature (by cooling) or changes in chemistry (by dissolving ethanol or ice in the brine) or can cause brines to become saturated with ethanol or ice. Data for this diagram come from Kousksou and others (2007).     Return to Diagram List