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  2. Activation - Wikipedia

    en.wikipedia.org/wiki/Activation

    In chemistry, "activation" refers to the reversible transition of a molecule into a nearly identical chemical or physical state, with the defining characteristic being that this resultant state exhibits an increased propensity to undergo a specified chemical reaction. Thus, activation is conceptually the opposite of protection, in which the ...

  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

    All chemical transformations pass through an unstable structure called the transition state, which is poised between the chemical structures of the substrates and products. The transition states for chemical reactions are proposed to have lifetimes near 10 −13 seconds, on the order of the time of a single bond vibration. No physical or ...

  5. 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 ( E a ) of a reaction is measured in kilojoules per mole (kJ/mol) or kilocalories per mole (kcal/mol). [ 2 ]

  6. Arrhenius plot - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_plot

    Arrhenius plots are often used to analyze the effect of temperature on the rates of chemical reactions. For a single rate-limited thermally activated process, an Arrhenius plot gives a straight line, from which the activation energy and the pre-exponential factor can both be determined.

  7. Sociobiology - Wikipedia

    en.wikipedia.org/wiki/Sociobiology

    Sociobiology is a field of biology that aims to explain social behavior in terms of evolution.It draws from disciplines including psychology, ethology, anthropology, evolution, zoology, archaeology, and population genetics.

  8. Carbon–hydrogen bond activation - Wikipedia

    en.wikipedia.org/wiki/Carbon–hydrogen_bond...

    This broader definition encompasses all reactions that would fall under the restricted definition of C–H activation given above. However, it also includes iron-catalyzed alkane C–H hydroxylation reactions that proceed through the oxygen rebound mechanism (e.g. cytochrome P450 enzymes and their synthetic analogues), in which an ...

  9. Chemical reaction - Wikipedia

    en.wikipedia.org/wiki/Chemical_reaction

    A chemical reaction is a process that leads to the chemical transformation of one ... Higher activation energy implies that the reactants need more energy to start ...