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  2. Elimination reaction - Wikipedia

    en.wikipedia.org/wiki/Elimination_reaction

    Elimination reaction of cyclohexanol to cyclohexene with sulfuric acid and heat [1] An elimination reaction is a type of organic reaction in which two substituents are removed from a molecule in either a one- or two-step mechanism. [2] The one-step mechanism is known as the E2 reaction, and the two-step mechanism is known as the E1 reaction ...

  3. Hammond's postulate - Wikipedia

    en.wikipedia.org/wiki/Hammond's_postulate

    In an E2 mechanism, a base takes a proton near the leaving group, forcing the electrons down to make a double bond, and forcing off the leaving group-all in one concerted step. The rate law depends on the first order concentration of two reactants, making it a 2nd order (bimolecular) elimination reaction.

  4. Entropy of activation - Wikipedia

    en.wikipedia.org/wiki/Entropy_of_activation

    for reactions in solution and unimolecular gas reactions A = (ek B T/h) exp(ΔS ‡ /R), while for bimolecular gas reactions A = (e 2 k B T/h) (RT/p) exp(ΔS ‡ /R). In these equations e is the base of natural logarithms, h is the Planck constant, k B is the Boltzmann constant and T the absolute temperature. R′ is the ideal gas constant. The ...

  5. Reactivity series - Wikipedia

    en.wikipedia.org/wiki/Reactivity_series

    The order of reactivity, as shown by the vigour of the reaction with water or the speed at which the metal surface tarnishes in air, appears to be Cs > K > Na > Li > alkaline earth metals, i.e., alkali metals > alkaline earth metals, the same as the reverse order of the (gas-phase) ionization energies.

  6. Activation strain model - Wikipedia

    en.wikipedia.org/wiki/Activation_strain_model

    The activation strain model was originally proposed and has been extensively developed by Bickelhaupt and coworkers. [4] This model breaks the potential energy curve as a function of reaction coordinate, ζ, of a reaction into 2 components as shown in equation 1: the energy due to straining the original reactant molecules (∆E strain) and the energy due to interaction between reactant ...

  7. Hughes–Ingold symbol - Wikipedia

    en.wikipedia.org/wiki/Hughes–Ingold_symbol

    A Hughes–Ingold symbol describes various details of the reaction mechanism and overall result of a chemical reaction. [1] For example, an S N 2 reaction is a substitution reaction ("S") by a nucleophilic process ("N") that is bimolecular ("2" molecular entities involved) in its rate-determining step.

  8. Reactivity (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Reactivity_(chemistry)

    The chemical reactivity of a substance can refer to the variety of circumstances (conditions that include temperature, pressure, presence of catalysts) in which it reacts, in combination with the: variety of substances with which it reacts, equilibrium point of the reaction (i.e., the extent to which all of it reacts), and; rate of the reaction.

  9. Collision theory - Wikipedia

    en.wikipedia.org/wiki/Collision_theory

    Nevertheless, some reactions exhibit steric factors greater than unity: the harpoon reactions, which involve atoms that exchange electrons, producing ions. The deviation from unity can have different causes: the molecules are not spherical, so different geometries are possible; not all the kinetic energy is delivered into the right spot; the ...