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  2. List of physical constants - Wikipedia

    en.wikipedia.org/wiki/List_of_physical_constants

    The constants listed here are known values of physical constants expressed in SI units; that is, physical quantities that are generally believed to be universal in nature and thus are independent of the unit system in which they are measured. Many of these are redundant, in the sense that they obey a known relationship with other physical ...

  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. Law of mass action - Wikipedia

    en.wikipedia.org/wiki/Law_of_mass_action

    The affinity constants, k + and k −, of the 1879 paper can now be recognised as rate constants. The equilibrium constant, K, was derived by setting the rates of forward and backward reactions to be equal. This also meant that the chemical affinities for the forward and backward reactions are equal. The resultant expression

  5. Gas constant - Wikipedia

    en.wikipedia.org/wiki/Gas_constant

    The molar gas constant (also known as the gas constant, universal gas constant, or ideal gas constant) is denoted by the symbol R or R. It is the molar equivalent to the Boltzmann constant , expressed in units of energy per temperature increment per amount of substance , rather than energy per temperature increment per particle .

  6. Activation energy - Wikipedia

    en.wikipedia.org/wiki/Activation_energy

    Some multistep reactions can also have apparent negative activation energies. For example, the overall rate constant k for a two-step reaction A ⇌ B, B → C is given by k = k 2 K 1, where k 2 is the rate constant of the rate-limiting slow second step and K 1 is the equilibrium constant of the rapid

  7. Reaction progress kinetic analysis - Wikipedia

    en.wikipedia.org/wiki/Reaction_progress_kinetic...

    A steady-state rate law contains all of the rate constants and species required to go from starting material to product, while the denominator consists of a sum of terms describing the relative rates of the forward and reverse reactions consuming the steady-state intermediate.

  8. Desorption - Wikipedia

    en.wikipedia.org/wiki/Desorption

    Using the equation for rate of desorption (Polyani Winer equation), one can find T p, and Redhead shows that the relationship between T p and E can be approximated to be linear, given that the ratio of the rate constant to the heating rate is within the range 10 8 – 10 13.

  9. Boltzmann constant - Wikipedia

    en.wikipedia.org/wiki/Boltzmann_constant

    Boltzmann constant: The Boltzmann constant, k, is one of seven fixed constants defining the International System of Units, the SI, with k = 1.380 649 x 10 −23 J K −1. The Boltzmann constant is a proportionality constant between the quantities temperature (with unit kelvin) and energy (with unit joule).