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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 (Ea) of a reaction is measured in kilojoules per mole (kJ/mol) or kilocalories per mole (kcal/mol). [2] Activation energy can be thought of as the magnitude ...

  3. Arrhenius equation - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_equation

    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 ...

  4. 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. The equation follows from the transition state ...

  5. Arrhenius plot - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_plot

    Arrhenius plot. In chemical kinetics, an Arrhenius plot displays the logarithm of a reaction rate constant, ( , ordinate axis) plotted against reciprocal of the temperature ( , abscissa). [1] Arrhenius plots are often used to analyze the effect of temperature on the rates of chemical reactions. For a single rate-limited thermally activated ...

  6. Bell–Evans–Polanyi principle - Wikipedia

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

    The Evans–Polanyi model is a linear energy relationship that serves as an efficient way to calculate activation energy of many reactions within a distinct family. 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 ...

  7. 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.

  8. 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 ...

  9. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    The free energy of activation, ΔG ‡, is defined in transition state theory to be the energy such that ‡ = ⁡ ‡ ′ holds. The parameters ΔH ‡ and ΔS ‡ can then be inferred by determining ΔG ‡ = ΔH ‡ – TΔS ‡ at different temperatures.