enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  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. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    The dependence on m correlates with the oxidation state of the central atom, X: the higher the oxidation state the stronger the oxyacid. For example, p K a for HClO is 7.2, for HClO 2 is 2.0, for HClO 3 is −1 and HClO 4 is a strong acid ( p K a ≪ 0 ). [ 7 ]

  4. Phosphate-buffered saline - Wikipedia

    en.wikipedia.org/wiki/Phosphate-buffered_saline

    Dependence of pKa2 of phosphate buffer on ionic strength and temperature The Henderson–Hasselbalch equation gives the pH of a solution relative to the p K a of the acid–base pair. However the p K a is dependent on ionic strength and temperature, and as it shifts so will the pH of a solution based on that acid–base pair.

  5. Temperature coefficient - Wikipedia

    en.wikipedia.org/wiki/Temperature_coefficient

    For strongly temperature-dependent α, this approximation is only useful for small temperature differences ΔT. Temperature coefficients are specified for various applications, including electric and magnetic properties of materials as well as reactivity. The temperature coefficient of most of the reactions lies between 2 and 3.

  6. Dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Dissociation_constant

    In chemistry, biochemistry, and pharmacology, a dissociation constant (K D) is a specific type of equilibrium constant that measures the propensity of a larger object to separate (dissociate) reversibly into smaller components, as when a complex falls apart into its component molecules, or when a salt splits up into its component ions.

  7. Thermodynamic databases for pure substances - Wikipedia

    en.wikipedia.org/wiki/Thermodynamic_databases...

    For example, values of the Gibbs energy obtained from high-temperature equilibrium emf methods must be identical to those calculated from calorimetric measurements of the enthalpy and entropy values. The database provider must use recognized data analysis procedures to resolve differences between data obtained by different types of experiments.

  8. Van 't Hoff equation - Wikipedia

    en.wikipedia.org/wiki/Van_'t_Hoff_equation

    The Van 't Hoff equation relates the change in the equilibrium constant, K eq, of a chemical reaction to the change in temperature, T, given the standard enthalpy change, Δ r H ⊖, for the process. The subscript r {\displaystyle r} means "reaction" and the superscript ⊖ {\displaystyle \ominus } means "standard".

  9. Equilibrium constant - Wikipedia

    en.wikipedia.org/wiki/Equilibrium_constant

    The concentration of the species LH is equal to the sum of the concentrations of the two micro-species with the same chemical formula, labelled L 1 H and L 2 H. The constant K 2 is for a reaction with these two micro-species as products, so that [LH] = [L 1 H] + [L 2 H] appears in the numerator, and it follows that this macro-constant is equal ...