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  2. Reaction rate - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate

    For gas phase reaction the rate equation is often alternatively expressed in terms of partial pressures. In these equations k ( T ) is the reaction rate coefficient or rate constant , although it is not really a constant, because it includes all the parameters that affect reaction rate, except for time and concentration.

  3. Grote–Hynes theory - Wikipedia

    en.wikipedia.org/wiki/Grote–Hynes_theory

    Grote–Hynes theory is a theory of reaction rate in a solution phase. This rate theory was developed by James T. Hynes with his graduate student Richard F. Grote in 1980. [1] The theory is based on the generalized Langevin equation (GLE). This theory introduced the concept of frequency dependent friction for

  4. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    An example of such a reaction is the ring closure of cyclopentane biradicals generated from the gas-phase thermal decomposition of 2,3-diazabicyclo[2.2.1]hept-2-ene. [ 20 ] [ 21 ] Transition state theory is also based on the assumption that atomic nuclei behave according to classical mechanics . [ 22 ]

  5. 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 ...

  6. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    As an example, consider the gas-phase reaction NO 2 + CO → NO + CO 2.If this reaction occurred in a single step, its reaction rate (r) would be proportional to the rate of collisions between NO 2 and CO molecules: r = k[NO 2][CO], where k is the reaction rate constant, and square brackets indicate a molar concentration.

  7. Heterogeneous catalysis - Wikipedia

    en.wikipedia.org/wiki/Heterogeneous_catalysis

    Heterogeneous catalysis typically involves solid phase catalysts and gas phase reactants. [2] In this case, there is a cycle of molecular adsorption, reaction, and desorption occurring at the catalyst surface. Thermodynamics, mass transfer, and heat transfer influence the rate (kinetics) of reaction.

  8. 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 ...

  9. Collision theory - Wikipedia

    en.wikipedia.org/wiki/Collision_theory

    The rate for a bimolecular gas-phase reaction, A + B → product, predicted by collision theory is [6] = = ⁡ ()where: k is the rate constant in units of (number of molecules) −1 ⋅s −1 ⋅m 3.