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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. Elasticity coefficient - Wikipedia

    en.wikipedia.org/wiki/Elasticity_coefficient

    A. The slope of the reaction rate versus the reactant concentration scaled by both the reactant concentration and reaction rate yields the elasticity. If the log of the reaction rate and the log of the reactant concentration is plotted, the elasticity can be read directly from the slope of the curve. Curves were generated by assuming v = s/(2 + s)

  5. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    A major use of the integrated equation is to estimate a new equilibrium constant at a new absolute temperature assuming a constant standard enthalpy change over the temperature range. To obtain the integrated equation, it is convenient to first rewrite the Van 't Hoff equation as [ 2 ]

  6. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    At 298 K, a reaction with ΔG ‡ = 23 kcal/mol has a rate constant of k ≈ 8.4 × 10 −5 s −1 and a half life of t 1/2 ≈ 2.3 hours, figures that are often rounded to k ~ 10 −4 s −1 and t 1/2 ~ 2 h. Thus, a free energy of activation of this magnitude corresponds to a typical reaction that proceeds to completion overnight at room ...

  7. Rate equation - Wikipedia

    en.wikipedia.org/wiki/Rate_equation

    In chemistry, the rate equation (also known as the rate law or empirical differential rate equation) is an empirical differential mathematical expression for the reaction rate of a given reaction in terms of concentrations of chemical species and constant parameters (normally rate coefficients and partial orders of reaction) only. [1]

  8. Hazen–Williams equation - Wikipedia

    en.wikipedia.org/wiki/Hazen–Williams_equation

    A result of adjusting the exponents is that the value of C appears more like a constant over a wide range of the other parameters. [8] The conversion factor k was chosen so that the values for C were the same as in the Chézy formula for the typical hydraulic slope of S=0.001. [9] The value of k is 0.001 −0.04. [10]

  9. Eyring equation - Wikipedia

    en.wikipedia.org/wiki/Eyring_equation

    To avoid specifying a value of , the rate constant can be compared to the value of the rate constant at some fixed reference temperature (i.e., / ()) which eliminates the factor in the resulting expression if one assumes that the transmission coefficient is independent of temperature.