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  2. Benzoic acid - Wikipedia

    en.wikipedia.org/wiki/Benzoic_acid

    Benzoic acid is cheap and readily available, so the laboratory synthesis of benzoic acid is mainly practiced for its pedagogical value. It is a common undergraduate preparation. Benzoic acid can be purified by recrystallization from water because of its high solubility in hot water and poor solubility in cold water. The avoidance of organic ...

  3. 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

  4. List of physical constants - Wikipedia

    en.wikipedia.org/wiki/List_of_physical_constants

    The constants listed here are known values of physical constants expressed in SI units; that is, physical quantities that are generally believed to be universal in nature and thus are independent of the unit system in which they are measured. Many of these are redundant, in the sense that they obey a known relationship with other physical ...

  5. Electron-withdrawing group - Wikipedia

    en.wikipedia.org/wiki/Electron-withdrawing_group

    EWGs enhance the Lewis acidity, making compounds more reactive as Lewis acids. For example, fluorine is a stronger electron-withdrawing substituent than methyl, resulting in an increased Lewis acidity of boron trifluoride relative to trimethylborane. Electron-withdrawing groups also tend to reduce Lewis basicity. [3]

  6. Van der Waals constants (data page) - Wikipedia

    en.wikipedia.org/wiki/Van_der_Waals_constants...

    The following table lists the Van der Waals constants (from the Van der Waals equation) for a number of common gases and volatile liquids. [ 1 ] To convert from L 2 b a r / m o l 2 {\displaystyle \mathrm {L^{2}bar/mol^{2}} } to L 2 k P a / m o l 2 {\displaystyle \mathrm {L^{2}kPa/mol^{2}} } , multiply by 100.

  7. Category:Physical constants - Wikipedia

    en.wikipedia.org/wiki/Category:Physical_constants

    Pages in category "Physical constants" The following 37 pages are in this category, out of 37 total. This list may not reflect recent changes. ...

  8. Ortho effect - Wikipedia

    en.wikipedia.org/wiki/Ortho_effect

    When a substituent group is located ortho position to the carboxyl group in a substituted benzoic acid compound, the compound becomes more acidic surpassing the unmodified benzoic acid. Generally ortho-substituted benzoic acids are stronger acids than their meta and para isomers.

  9. Van 't Hoff factor - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_factor

    For example, carboxylic acids such as acetic acid (ethanoic acid) or benzoic acid form dimers in benzene, so that the number of solute particles is half the number of acid molecules. When solute particles dissociate in solution, i is greater than 1 (e.g. sodium chloride in water, potassium chloride in water, magnesium chloride in water).