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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. 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.

  4. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    For a condensed-phase (e.g., solution-phase) or unimolecular gas-phase reaction step, E a = ΔH ‡ + RT. For other gas-phase reactions, E a = ΔH ‡ + (1 − Δn ‡)RT, where Δn ‡ is the change in the number of molecules on forming the transition state. [15] (Thus, for a bimolecular gas-phase process, E a = ΔH ‡ + 2RT.)

  5. 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

  6. 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 ...

  7. 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.

  8. Gas-phase ion chemistry - Wikipedia

    en.wikipedia.org/wiki/Gas-phase_ion_chemistry

    Gas phase ion chemistry is a field of science encompassed within both chemistry and physics. It is the science that studies ions and molecules in the gas phase, most often enabled by some form of mass spectrometry. By far the most important applications for this science is in studying the thermodynamics and kinetics of reactions.

  9. Damköhler numbers - Wikipedia

    en.wikipedia.org/wiki/Damköhler_numbers

    From the general mole balance on some species , where for a CSTR steady state and perfect mixing are assumed, + = + = = Assuming a constant volumetric flow rate , which is the case for a liquid reactor or a gas phase reaction with no net generation of moles,