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  2. 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 ...

  3. 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 ...

  4. Sigmoid function - Wikipedia

    en.wikipedia.org/wiki/Sigmoid_function

    A wide variety of sigmoid functions including the logistic and hyperbolic tangent functions have been used as the activation function of artificial neurons. Sigmoid curves are also common in statistics as cumulative distribution functions (which go from 0 to 1), such as the integrals of the logistic density , the normal density , and Student's ...

  5. Arrhenius plot - Wikipedia

    en.wikipedia.org/wiki/Arrhenius_plot

    Substituting for the quotient in the exponent of : / = where the approximate value for R is 8.31446 J K −1 mol −1 The activation energy of this reaction from these data is then: E a = R × 12,667 K = 105,300 J mol −1 = 105.3 kJ mol −1 .

  6. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    where: k 1 is the rate coefficient for the reaction that consumes A and B; k −1 is the rate coefficient for the backwards reaction, which consumes P and Q and produces A and B. The constants k 1 and k −1 are related to the equilibrium coefficient for the reaction (K) by the following relationship (set v =0 in balance):

  7. Reaction rate - Wikipedia

    en.wikipedia.org/wiki/Reaction_rate

    Iron rusting has a low reaction rate. This process is slow. Wood combustion has a high reaction rate. This process is fast. The reaction rate or rate of reaction is the speed at which a chemical reaction takes place, defined as proportional to the increase in the concentration of a product per unit time and to the decrease in the concentration of a reactant per unit time. [1]

  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. Damköhler numbers - Wikipedia

    en.wikipedia.org/wiki/Damköhler_numbers

    Since the reaction rate determines the reaction timescale, the exact formula for the Damköhler number varies according to the rate law equation. For a general chemical reaction A → B following the Power law kinetics of n-th order , the Damköhler number for a convective flow system is defined as: