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  2. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    For a chemical reaction to proceed at a reasonable rate, the temperature of the system should be high enough such that there exists an appreciable number of molecules with translational energy equal to or greater than the activation energy. The term "activation energy" was introduced in 1889 by the Swedish scientist Svante Arrhenius. [3]

  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. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    The rate constant expression from transition state theory can be used to calculate the ΔG ‡, ΔH ‡, ΔS ‡, and even ΔV ‡ (the volume of activation) using experimental rate data. These so-called activation parameters give insight into the nature of a transition state, including energy content and degree of order, compared to the ...

  5. 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 ...

  6. Reaction rate - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate

    Iron rusting has a low reaction rate. This process is slow. Wood combustion has a high reaction rate. This process is fast. The reaction rate or rate of reaction is the speed at which a chemical reaction takes place, defined as proportional to the increase in the concentration of a product per unit time and to the decrease in the concentration of a reactant per unit time. [1]

  7. Chemical kinetics - Wikipedia

    en.wikipedia.org/wiki/Chemical_kinetics

    The rate coefficients and products of many high-temperature gas-phase reactions change if an inert gas is added to the mixture; variations on this effect are called fall-off and chemical activation. These phenomena are due to exothermic or endothermic reactions occurring faster than heat transfer, causing the reacting molecules to have non ...

  8. Collision theory - Wikipedia

    en.wikipedia.org/wiki/Collision_theory

    Collision theory is a principle of chemistry used to predict the rates of chemical reactions. It states that when suitable particles of the reactant hit each other with the correct orientation, only a certain amount of collisions result in a perceptible or notable change; these successful changes are called successful collisions.

  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 ...