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  2. Substitution reaction - Wikipedia

    en.wikipedia.org/wiki/Substitution_reaction

    Substitution reactions in organic chemistry are classified either as electrophilic or nucleophilic depending upon the reagent involved, whether a reactive intermediate involved in the reaction is a carbocation, a carbanion or a free radical, and whether the substrate is aliphatic or aromatic. Detailed understanding of a reaction type helps to ...

  3. Reaction intermediate - Wikipedia

    en.wikipedia.org/wiki/Reaction_intermediate

    In chemistry, a reaction intermediate, or intermediate, is a molecular entity arising within the sequence of a stepwise chemical reaction. It is formed as the reaction product of an elementary step, from the reactants and/or preceding intermediates, but is consumed in a later step. It does not appear in the chemical equation for the overall ...

  4. Integration by substitution - Wikipedia

    en.wikipedia.org/wiki/Integration_by_substitution

    In calculus, integration by substitution, also known as u-substitution, reverse chain rule or change of variables, [1] is a method for evaluating integrals and antiderivatives. It is the counterpart to the chain rule for differentiation , and can loosely be thought of as using the chain rule "backwards."

  5. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    Instead, the slow step involves two molecules of NO 2. A possible mechanism for the overall reaction that explains the rate law is: 2 NO 2 → NO 3 + NO (slow) NO 3 + CO → NO 2 + CO 2 (fast) Each step is called an elementary step, and each has its own rate law and molecularity. The sum of the elementary steps gives the net reaction.

  6. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    Even though the theory is widely applicable, it does have limitations. For example, when applied to each elementary step of a multi-step reaction, the theory assumes that each intermediate is long-lived enough to reach a Boltzmann distribution of energies before continuing to the next step. When the intermediates are very short-lived, TST fails ...

  7. Integration by reduction formulae - Wikipedia

    en.wikipedia.org/wiki/Integration_by_reduction...

    In integral calculus, integration by reduction formulae is a method relying on recurrence relations.It is used when an expression containing an integer parameter, usually in the form of powers of elementary functions, or products of transcendental functions and polynomials of arbitrary degree, can't be integrated directly.

  8. Hammett equation - Wikipedia

    en.wikipedia.org/wiki/Hammett_equation

    In organic chemistry, the Hammett equation describes a linear free-energy relationship relating reaction rates and equilibrium constants for many reactions involving benzoic acid derivatives with meta- and para-substituents to each other with just two parameters: a substituent constant and a reaction constant.

  9. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    Another example is the unimolecular nucleophilic substitution (S N 1) reaction in organic chemistry, where it is the first, rate-determining step that is unimolecular. A specific case is the basic hydrolysis of tert-butyl bromide (t-C 4 H 9 Br) by aqueous sodium hydroxide. The mechanism has two steps (where R denotes the tert-butyl radical t-C ...