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  2. 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 ...

  3. 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 ...

  4. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    If the concentration of a reactant remains constant (because it is a catalyst, or because it is in great excess with respect to the other reactants), its concentration can be included in the rate constant, leading to a pseudo–first-order (or occasionally pseudo–second-order) rate equation. For a typical second-order reaction with rate ...

  5. Half-life - Wikipedia

    en.wikipedia.org/wiki/Half-life

    [] = [] In order to find the half-life, we have to replace the concentration value for the initial concentration divided by 2: [] / = [] / and isolate the time: / = [] This t ½ formula indicates that the half-life for a zero order reaction depends on the initial concentration and the rate constant.

  6. Zero order - Wikipedia

    en.wikipedia.org/wiki/Zero_order

    Zero order reaction. Zero-order process (statistics), a sequence of random variables, each independent of the previous ones; Zero order process (chemistry), a chemical reaction in which the rate of change of concentration is independent of the concentrations; Zeroth-order approximation, an approximation of a function by a constant

  7. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    In fact, however, the observed reaction rate is second-order in NO 2 and zero-order in CO, [5] with rate equation r = k[NO 2] 2. This suggests that the rate is determined by a step in which two NO 2 molecules react, with the CO molecule entering at another, faster, step. A possible mechanism in two elementary steps that explains the rate ...

  8. Chemical kinetics - Wikipedia

    en.wikipedia.org/wiki/Chemical_kinetics

    Chemical kinetics, also known as reaction kinetics, is the branch of physical chemistry that is concerned with understanding the rates of chemical reactions. It is different from chemical thermodynamics, which deals with the direction in which a reaction occurs but in itself tells nothing about its rate.

  9. Pre-exponential factor - Wikipedia

    en.wikipedia.org/wiki/Pre-exponential_factor

    In chemical kinetics, the pre-exponential factor or A factor is the pre-exponential constant in the Arrhenius equation (equation shown below), an empirical relationship between temperature and rate coefficient. It is usually designated by A when determined from experiment, while Z is usually left for collision frequency. The pre-exponential ...