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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. Arrhenius equation - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_equation

    If the reaction is first order it has the unit s −1, and for that reason it is often called the frequency factor or attempt frequency of the reaction. Most simply, k is the number of collisions that result in a reaction per second, A is the number of collisions (leading to a reaction or not) per second occurring with the proper orientation to ...

  4. Law of mass action - Wikipedia

    en.wikipedia.org/wiki/Law_of_mass_action

    The affinity constants, k + and k −, of the 1879 paper can now be recognised as rate constants. The equilibrium constant, K, was derived by setting the rates of forward and backward reactions to be equal. This also meant that the chemical affinities for the forward and backward reactions are equal. The resultant expression

  5. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    According to transition state theory, the smallest fraction of the catalytic cycle is spent in the most important step, that of the transition state. The original proposals of absolute reaction rate theory for chemical reactions defined the transition state as a distinct species in the reaction coordinate that determined the absolute reaction rate.

  6. 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):

  7. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    The Van 't Hoff equation relates the change in the equilibrium constant, K eq, of a chemical reaction to the change in temperature, T, given the standard enthalpy change, Δ r H ⊖, for the process. The subscript r {\displaystyle r} means "reaction" and the superscript ⊖ {\displaystyle \ominus } means "standard".

  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. 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 ...