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This page contains tables of azeotrope data for various binary and ternary mixtures of solvents. The data include the composition of a mixture by weight (in binary azeotropes, when only one fraction is given, it is the fraction of the second component), the boiling point (b.p.) of a component, the boiling point of a mixture, and the specific gravity of the mixture.
The annotation, d a°C/b°C, indicates density of solution at temperature a divided by density of pure water at temperature b known as specific gravity. When temperature b is 4 °C, density of water is 0.999972 g/mL.
Water: 0 Ice: Ammonium chloride-5 0.3 to 1 ratio of salt to ice. Liquid N 2: Aniline-6 Ice: Sodium thiosulfate pentahydrate-8 1.1 to 1 ratio of salt to ice. Ice: Calcium chloride hexahydrate-10 1 to 2.5 ratio of salt to ice. Liquid N 2: Ethylene glycol-10 Ice: Acetone-10 1 to 1 ratio of acetone to ice. Liquid N 2: Cycloheptane-12 Dry ice ...
As water or ethylene glycol freeze out of the mixture, the concentration of ethanol/methanol increases. This leads to a new, lower freezing point. With dry ice, these baths will never freeze solid, as pure methanol and ethanol both freeze below −78 °C (−98 °C and −114 °C respectively).
This Wikipedia page provides a comprehensive list of boiling and freezing points for various solvents.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
A well-known example of a positive azeotrope is an ethanol–water mixture (obtained by fermentation of sugars) consisting of 95.63% ethanol and 4.37% water (by mass), which boils at 78.2 °C. [10] Ethanol boils at 78.4 °C, water boils at 100 °C, but the azeotrope boils at 78.2 °C, which is lower than either of its constituents. [11]
Thus water behaves like a water–methanol mixture between 100 °C and 200 °C. Disruption of extended hydrogen bonding allows molecules to move more freely (viscosity, diffusion and surface tension effects), and extra energy must be supplied to break the bonds (increased heat capacity).