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  2. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    In the Arrhenius model of reaction rates, activation energy is the minimum amount of energy that must be available to reactants for a chemical reaction to occur. [1] The activation energy ( E a ) of a reaction is measured in kilojoules per mole (kJ/mol) or kilocalories per mole (kcal/mol). [ 2 ]

  3. Activated complex - Wikipedia

    en.wikipedia.org/wiki/Activated_complex

    The activation energy is the minimum amount of energy to initiate a chemical reaction and form the activated complex. [6] The energy serves as a threshold that reactant molecules must surpass to overcome the energy barrier and transition into the activated complex.

  4. Arrhenius equation - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_equation

    In physical chemistry, the Arrhenius equation is a formula for the temperature dependence of reaction rates.The equation was proposed by Svante Arrhenius in 1889, based on the work of Dutch chemist Jacobus Henricus van 't Hoff who had noted in 1884 that the van 't Hoff equation for the temperature dependence of equilibrium constants suggests such a formula for the rates of both forward and ...

  5. Collision theory - Wikipedia

    en.wikipedia.org/wiki/Collision_theory

    The successful collisions must have enough energy, also known as activation energy, at the moment of impact to break the pre-existing bonds and form all new bonds. This results in the products of the reaction. The activation energy is often predicted using the Transition state theory. Increasing the concentration of the reactant brings about ...

  6. Activation - Wikipedia

    en.wikipedia.org/wiki/Activation

    The energy of activation [1] specifies the amount of free energy the reactants must possess (in addition to their rest energy) in order to initiate their conversion into corresponding products—that is, in order to reach the transition state for the reaction. The energy needed for activation can be quite small, and often it is provided by the ...

  7. Eyring equation - Wikipedia

    en.wikipedia.org/wiki/Eyring_equation

    The Eyring equation (occasionally also known as Eyring–Polanyi equation) is an equation used in chemical kinetics to describe changes in the rate of a chemical reaction against temperature. It was developed almost simultaneously in 1935 by Henry Eyring , Meredith Gwynne Evans and Michael Polanyi .

  8. Bell–Evans–Polanyi principle - Wikipedia

    en.wikipedia.org/wiki/Bell–Evans–Polanyi...

    The activation energy may be used to characterize the kinetic rate parameter of a given reaction through application of the Arrhenius equation. The Evans–Polanyi model assumes that the pre-exponential factor of the Arrhenius equation and the position of the transition state along the reaction coordinate are the same for all reactions ...

  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 ...