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  2. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    where ln denotes the natural logarithm, is the thermodynamic equilibrium constant, and R is the ideal gas constant.This equation is exact at any one temperature and all pressures, derived from the requirement that the Gibbs free energy of reaction be stationary in a state of chemical equilibrium.

  3. Rate-determining step - Wikipedia

    en.wikipedia.org/wiki/Rate-determining_step

    As an example, consider the gas-phase reaction NO 2 + CO → NO + CO 2.If this reaction occurred in a single step, its reaction rate (r) would be proportional to the rate of collisions between NO 2 and CO molecules: r = k[NO 2][CO], where k is the reaction rate constant, and square brackets indicate a molar concentration.

  4. Determination of equilibrium constants - Wikipedia

    en.wikipedia.org/wiki/Determination_of...

    The relationship between a species' concentration and the measured quantity is specific for the measurement technique, as indicated in each section above. Using this relationship, the set of parameters, the stability constant values and values of properties such as molar absorptivity or specified chemical shifts, may be refined by a non-linear ...

  5. Shewhart individuals control chart - Wikipedia

    en.wikipedia.org/wiki/Shewhart_individuals...

    For processes that produce homogeneous batches (e.g., chemical) where repeat measurements vary primarily because of measurement error; The "chart" actually consists of a pair of charts: one, the individuals chart, displays the individual measured values; the other, the moving range chart, displays the difference from one point to the next.

  6. Equilibrium constant - Wikipedia

    en.wikipedia.org/wiki/Equilibrium_constant

    The free energy change, dG r, can be expressed as a weighted sum of change in amount times the chemical potential, the partial molar free energy of the species. The chemical potential, μ i , of the i th species in a chemical reaction is the partial derivative of the free energy with respect to the number of moles of that species, N i

  7. Transition state theory - Wikipedia

    en.wikipedia.org/wiki/Transition_state_theory

    Using the Eyring equation, there is a straightforward relationship between ΔG ‡, first-order rate constants, and reaction half-life at a given temperature. At 298 K, a reaction with Δ G ‡ = 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 ...

  8. Stability constants of complexes - Wikipedia

    en.wikipedia.org/wiki/Stability_constants_of...

    Jannik Bjerrum (son of Niels Bjerrum) developed the first general method for the determination of stability constants of metal-ammine complexes in 1941. [1] The reasons why this occurred at such a late date, nearly 50 years after Alfred Werner had proposed the correct structures for coordination complexes, have been summarised by Beck and Nagypál. [2]

  9. 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 ...