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  2. SN1 reaction - Wikipedia

    en.wikipedia.org/wiki/SN1_reaction

    the simple first-order rate law described in introductory textbooks. Under these conditions, the concentration of the nucleophile does not affect the rate of the reaction, and changing the nucleophile (e.g. from H 2 O to MeOH) does not affect the reaction rate, though the product is, of course, different. In this regime, the first step ...

  3. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    In chemistry, the rate equation (also known as the rate law or empirical differential rate equation) is an empirical differential mathematical expression for the reaction rate of a given reaction in terms of concentrations of chemical species and constant parameters (normally rate coefficients and partial orders of reaction) only. [1]

  4. SN1CB mechanism - Wikipedia

    en.wikipedia.org/wiki/Sn1CB_mechanism

    The rate law for the reaction is: = [() +] [] The rate law is deceptive: hydroxide serves not as a nucleophile but as a base to deprotonate the coordinated ammonia. Simultaneously with deprotonation, the halide dissociates.

  5. Nucleophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_substitution

    The rate equation for this reaction would be Rate=k[Sub][Nuc]. For a S N 2 reaction, an aprotic solvent is best, such as acetone, DMF, or DMSO. Aprotic solvents do not add protons (H + ions) into solution; if protons were present in S N 2 reactions, they would react with the nucleophile and severely limit the reaction rate. Since this reaction ...

  6. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    The rate law depends on the first order concentration of two reactants, making it a 2nd order (bimolecular) elimination reaction. Factors that affect the rate determining step are stereochemistry, leaving groups, and base strength. A theory, for an E2 reaction, by Joseph Bunnett suggests the lowest pass through the energy barrier between ...

  7. Substitution reaction - Wikipedia

    en.wikipedia.org/wiki/Substitution_reaction

    The two reactions are named according tho their rate law, with S N 1 having a first-order rate law, and S N 2 having a second-order. [2] S N 1 reaction mechanism occurring through two steps. The S N 1 mechanism has two steps. In the first step, the leaving group departs, forming a carbocation (C +). In the second step, the nucleophilic reagent ...

  8. Chemical kinetics - Wikipedia

    en.wikipedia.org/wiki/Chemical_kinetics

    Chemical kinetics, also known as reaction kinetics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is different from chemical thermodynamics, which deals with the direction in which a reaction occurs but in itself tells nothing about its rate.

  9. Associative substitution - Wikipedia

    en.wikipedia.org/wiki/Associative_substitution

    The first step is typically rate determining. Thus, the entropy of activation is negative, which indicates an increase in order in the system. These reactions follow second order kinetics: the rate of the appearance of product depends on the concentration of MX 4 and Y. The rate law is governed by the Eigen–Wilkins Mechanism.