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  2. Azeotrope tables - Wikipedia

    en.wikipedia.org/wiki/Azeotrope_tables

    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.

  3. Trouton's rule - Wikipedia

    en.wikipedia.org/wiki/Trouton's_rule

    [2] [3] It is valid for many liquids; for instance, the entropy of vaporization of toluene is 87.30 J/(K·mol), that of benzene is 89.45 J/(K·mol), and that of chloroform is 87.92 J/(K·mol). Because of its convenience, the rule is used to estimate the enthalpy of vaporization of liquids whose boiling points are known.

  4. Partition coefficient - Wikipedia

    en.wikipedia.org/wiki/Partition_coefficient

    K ow, being a type of partition coefficient, serves as a measure of the relationship between lipophilicity (fat solubility) and hydrophilicity (water solubility) of a substance. The value is greater than one if a substance is more soluble in fat-like solvents such as n-octanol, and less than one if it is more soluble in water. [citation needed]

  5. Azeotrope - Wikipedia

    en.wikipedia.org/wiki/Azeotrope

    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]

  6. Triple point of water - Wikipedia

    en.wikipedia.org/wiki/Triple_point

    A typical phase diagram.The solid green line applies to most substances; the dashed green line gives the anomalous behavior of water. In thermodynamics, the triple point of a substance is the temperature and pressure at which the three phases (gas, liquid, and solid) of that substance coexist in thermodynamic equilibrium. [1]

  7. Azeotropic distillation - Wikipedia

    en.wikipedia.org/wiki/Azeotropic_distillation

    The addition of a material separation agent, such as benzene to an ethanol/water mixture, changes the molecular interactions and eliminates the azeotrope. Added in the liquid phase, the new component can alter the activity coefficient of various compounds in different ways thus altering a mixture's relative volatility.

  8. Hammett equation - Wikipedia

    en.wikipedia.org/wiki/Hammett_equation

    The starting point for the collection of the substituent constants is a chemical equilibrium for which the substituent constant is arbitrarily set to 0 and the reaction constant is set to 1: the deprotonation of benzoic acid or benzene carboxylic acid (R and R' both H) in water at 25 °C. Scheme 1. Dissociation of benzoic acids

  9. Freezing-point depression - Wikipedia

    en.wikipedia.org/wiki/Freezing-point_depression

    In a similar manner, the chemical potential of the vapor above the solution is lower than that above a pure solvent, which results in boiling-point elevation. Freezing-point depression is what causes sea water (a mixture of salt and other compounds in water) to remain liquid at temperatures below 0 °C (32 °F), the freezing point of pure water.