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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. 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 ...

  4. 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

  5. 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. ...

  6. Taft equation - Wikipedia

    en.wikipedia.org/wiki/Taft_equation

    where log(k s /k CH 3) B is the ratio of the rate of the base catalyzed reaction compared to the reference reaction, log(k s /k CH 3) A is ratio of a rate of the acid catalyzed reaction compared to the reference reaction, and ρ* is a reaction constant that describes the sensitivity of the reaction series. For the definition reaction series, ρ ...

  7. Benzoyl chloride - Wikipedia

    en.wikipedia.org/wiki/Benzoyl_chloride

    Benzoyl chloride is produced from benzotrichloride using either water or benzoic acid: [2] C 6 H 5 CCl 3 + H 2 O → C 6 H 5 COCl + 2 HCl C 6 H 5 CCl 3 + C 6 H 5 CO 2 H → 2 C 6 H 5 COCl + HCl. As with other acyl chlorides, it can be generated from the parent acid and standard chlorinating agents such as phosphorus pentachloride, thionyl ...

  8. 4-Hydroxybenzoic acid - Wikipedia

    en.wikipedia.org/wiki/4-Hydroxybenzoic_acid

    4-Hydroxybenzoic acid, also known as p-hydroxybenzoic acid (PHBA), is a monohydroxybenzoic acid, a phenolic derivative of benzoic acid.It is a white crystalline solid that is slightly soluble in water and chloroform but more soluble in polar organic solvents such as alcohols and acetone. 4-Hydroxybenzoic acid is primarily known as the basis for the preparation of its esters, known as parabens ...

  9. 2-Chlorobenzoic acid - Wikipedia

    en.wikipedia.org/wiki/2-Chlorobenzoic_acid

    2-Chlorobenzoic acid is an organic compound with the formula ClC 6 H 4 CO 2 H. It is one of three isomeric chlorobenzoic acids , the one that is the strongest acid. This white solid is used as a precursor to a variety of drugs, food additives, and dyes.