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  2. Lewis structure - Wikipedia

    en.wikipedia.org/wiki/Lewis_structure

    [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond. Lewis structures show each atom and its position in the structure of the molecule using its chemical symbol.

  3. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...

  4. Lewis number - Wikipedia

    en.wikipedia.org/wiki/Lewis_number

    It is named after Warren K. Lewis (1882–1975), [6] [7] who was the first head of the Chemical Engineering Department at MIT. Some workers in the field of combustion assume (incorrectly) that the Lewis number was named for Bernard Lewis (1899–1993), who for many years was a major figure in the field of combustion research. [citation needed]

  5. SN2 reaction - Wikipedia

    en.wikipedia.org/wiki/SN2_reaction

    Competition experiment between SN2 and E2. With ethyl bromide, the reaction product is predominantly the substitution product. As steric hindrance around the electrophilic center increases, as with isobutyl bromide, substitution is disfavored and elimination is the predominant reaction. Other factors favoring elimination are the strength of the ...

  6. Nitrite - Wikipedia

    en.wikipedia.org/wiki/Nitrite

    In organic chemistry, alkyl nitrites are esters of nitrous acid and contain the nitrosoxy functional group. Nitro compounds contain the C–NO 2 group. Nitrites have the general formula RONO, where R is an aryl or alkyl group. Amyl nitrite and other alkyl nitrites have a vasodilating action and must be handled in the laboratory with caution ...

  7. Lewis acid catalysis - Wikipedia

    en.wikipedia.org/wiki/Lewis_Acid_Catalysis

    Two common modes of Lewis acid catalysis in reactions with polar mechanisms. In reactions with polar mechanisms, Lewis acid catalysis often involves binding of the catalyst to Lewis basic heteroatoms and withdrawing electron density, which in turn facilitates heterolytic bond cleavage (in the case of Friedel-Crafts reaction) or directly activates the substrate toward nucleophilic attack (in ...

  8. Lewis acids and bases - Wikipedia

    en.wikipedia.org/wiki/Lewis_acids_and_bases

    The model assigned E and C parameters to many Lewis acids and bases. Each acid is characterized by an E A and a C A. Each base is likewise characterized by its own E B and C B. The E and C parameters refer, respectively, to the electrostatic and covalent contributions to the strength of the bonds that the acid and base will form. The equation is

  9. Chemical equation - Wikipedia

    en.wikipedia.org/wiki/Chemical_equation

    A chemical equation is the symbolic representation of a chemical reaction in the form of symbols and chemical formulas.The reactant entities are given on the left-hand side and the product entities are on the right-hand side with a plus sign between the entities in both the reactants and the products, and an arrow that points towards the products to show the direction of the reaction. [1]