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  2. Kinetic isotope effect - Wikipedia

    en.wikipedia.org/wiki/Kinetic_isotope_effect

    A primary kinetic isotope effect (PKIE) may be found when a bond to the isotopically labeled atom is being formed or broken. [3] [4]: 427 Depending on the way a KIE is probed (parallel measurement of rates vs. intermolecular competition vs. intramolecular competition), the observation of a PKIE is indicative of breaking/forming a bond to the isotope at the rate-limiting step, or subsequent ...

  3. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    where: k 1 is the rate coefficient for the reaction that consumes A and B; k −1 is the rate coefficient for the backwards reaction, which consumes P and Q and produces A and B. The constants k 1 and k −1 are related to the equilibrium coefficient for the reaction (K) by the following relationship (set v=0 in balance):

  4. Reaction rate constant - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate_constant

    where A and B are reactants C is a product a, b, and c are stoichiometric coefficients,. the reaction rate is often found to have the form: = [] [] Here ⁠ ⁠ is the reaction rate constant that depends on temperature, and [A] and [B] are the molar concentrations of substances A and B in moles per unit volume of solution, assuming the reaction is taking place throughout the volume of the ...

  5. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    At 298 K, a reaction with ΔG ‡ = 23 kcal/mol has a rate constant of k ≈ 8.4 × 10 −5 s −1 and a half life of t 1/2 ≈ 2.3 hours, figures that are often rounded to k ~ 10 −4 s −1 and t 1/2 ~ 2 h. Thus, a free energy of activation of this magnitude corresponds to a typical reaction that proceeds to completion overnight at room ...

  6. Six factor formula - Wikipedia

    en.wikipedia.org/wiki/Six_factor_formula

    The multiplication factor, k, is defined as (see nuclear chain reaction): k = ⁠ number of neutrons in one generation / number of neutrons in preceding generation ⁠ If k is greater than 1, the chain reaction is supercritical, and the neutron population will grow exponentially. If k is less than 1, the chain reaction is subcritical, and the ...

  7. Dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Dissociation_constant

    In chemistry, biochemistry, and pharmacology, a dissociation constant (K D) is a specific type of equilibrium constant that measures the propensity of a larger object to separate (dissociate) reversibly into smaller components, as when a complex falls apart into its component molecules, or when a salt splits up into its component ions.

  8. Four factor formula - Wikipedia

    en.wikipedia.org/wiki/Four_factor_formula

    If k = 1, the chain reaction is critical and the neutron population will remain constant. In an infinite medium, neutrons cannot leak out of the system and the multiplication factor becomes the infinite multiplication factor, k = k ∞ {\displaystyle k=k_{\infty }} , which is approximated by the four-factor formula.

  9. 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 ...