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  2. Acid dissociation constant - Wikipedia

    en.wikipedia.org/wiki/Acid_dissociation_constant

    The K b values for dissociation of spermine protonated at one or other of the sites are examples of micro-constants. They cannot be determined directly by means of pH, absorbance, fluorescence or NMR measurements; a measured K b value is the sum of the K values for the micro-reactions.

  3. Absorption rate constant - Wikipedia

    en.wikipedia.org/wiki/Absorption_rate_constant

    The absorption rate constant K a is a value used in pharmacokinetics to describe the rate at which a drug enters into the system. It is expressed in units of time −1. [1] The K a is related to the absorption half-life (t 1/2a) per the following equation: K a = ln(2) / t 1/2a.

  4. Boiling-point elevation - Wikipedia

    en.wikipedia.org/wiki/Boiling-point_elevation

    K b, the ebullioscopic constant, which is dependent on the properties of the solvent. It can be calculated as K b = RT b 2 M/ΔH v, where R is the gas constant, and T b is the boiling temperature of the pure solvent [in K], M is the molar mass of the solvent, and ΔH v is the heat of vaporization per mole of the solvent.

  5. Henderson–Hasselbalch equation - Wikipedia

    en.wikipedia.org/wiki/Henderson–Hasselbalch...

    In chemistry and biochemistry, the Henderson–Hasselbalch equation = + ⁡ ([] []) relates the pH of a chemical solution of a weak acid to the numerical value of the acid dissociation constant, K a, of acid and the ratio of the concentrations, [] [] of the acid and its conjugate base in an equilibrium.

  6. Gran plot - Wikipedia

    en.wikipedia.org/wiki/Gran_plot

    The Gran plot is based on the Nernst equation which can be written as = + ⁡ {+} where E is a measured electrode potential, E 0 is a standard electrode potential, s is the slope, ideally equal to RT/nF, and {H +} is the activity of the hydrogen ion.

  7. Isothermal titration calorimetry - Wikipedia

    en.wikipedia.org/wiki/Isothermal_Titration...

    [1] [2] ITC is the only technique capable comprehensively characterizing thermodynamic and even kinetic profile of the interaction by simultaneously determining binding constants (Ka), reaction stoichiometry (n), enthalpy (ΔH) and entropy (ΔS) within a single experiment. [3] [4] [5] It consists of two cells which are enclosed in an adiabatic ...

  8. Activity coefficient - Wikipedia

    en.wikipedia.org/wiki/Activity_coefficient

    In thermodynamics, an activity coefficient is a factor used to account for deviation of a mixture of chemical substances from ideal behaviour. [1] In an ideal mixture, the microscopic interactions between each pair of chemical species are the same (or macroscopically equivalent, the enthalpy change of solution and volume variation in mixing is zero) and, as a result, properties of the mixtures ...

  9. Weak base - Wikipedia

    en.wikipedia.org/wiki/Weak_base

    A smaller H + concentration means a greater OH − concentration and, therefore, a greater K b and a greater pH. NaOH (s) (sodium hydroxide) is a stronger base than (CH 3 CH 2) 2 NH (l) (diethylamine) which is a stronger base than NH 3 (g) (ammonia). As the bases get weaker, the smaller the K b values become. [1]