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  2. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    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 ...

  3. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    Here k is the first-order rate constant, having dimension 1/time, [A](t) is the concentration at a time t and [A] 0 is the initial concentration. The rate of a first-order reaction depends only on the concentration and the properties of the involved substance, and the reaction itself can be described with a characteristic half-life. More than ...

  4. Arrhenius equation - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_equation

    This has the same form as an equation for a straight line: = +, where x is the reciprocal of T. So, when a reaction has a rate constant obeying the Arrhenius equation, a plot of ln k versus T −1 gives a straight line, whose slope and intercept can be used to determine E a and A respectively. This procedure is common in experimental chemical ...

  5. SN1 reaction - Wikipedia

    en.wikipedia.org/wiki/SN1_reaction

    A reaction mechanism was first introduced by Christopher Ingold et al. in 1940. [3] This reaction does not depend much on the strength of the nucleophile, unlike the S N 2 mechanism. This type of mechanism involves two steps. The first step is the ionization of alkyl halide in the presence of aqueous acetone or ethyl alcohol.

  6. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    In fact, however, the observed reaction rate is second-order in NO 2 and zero-order in CO, [5] with rate equation r = k[NO 2] 2. This suggests that the rate is determined by a step in which two NO 2 molecules react, with the CO molecule entering at another, faster, step. A possible mechanism in two elementary steps that explains the rate ...

  7. SN2 reaction - Wikipedia

    en.wikipedia.org/wiki/SN2_reaction

    In the S N 2 reaction, a strong nucleophile forms a new bond to an sp 3 -hybridised carbon atom via a backside attack, all while the leaving group detaches from the reaction center in a concerted (i.e. simultaneous) fashion. The name S N 2 refers to the Hughes-Ingold symbol of the mechanism: "S N " indicates that the reaction is a nucleophilic ...

  8. Nucleophilic substitution - Wikipedia

    en.wikipedia.org/wiki/Nucleophilic_substitution

    The two main mechanisms were the S N 1 reaction and the S N 2 reaction, where S stands for substitution, N stands for nucleophilic, and the number represents the kinetic order of the reaction. [4] In the S N 2 reaction, the addition of the nucleophile and the elimination of leaving group take place simultaneously (i.e. a concerted reaction).

  9. Reaction mechanism - Wikipedia

    en.wikipedia.org/wiki/Reaction_mechanism

    In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical reaction occurs. [1] A chemical mechanism is a theoretical conjecture that tries to describe in detail what takes place at each stage of an overall chemical reaction. The detailed steps of a reaction are not observable in most cases ...