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Thermodynamic Quantities for the Ionization Reactions of Buffers in Water



Robert N. Goldberg, N Kishore, R M. Lennen


This table contains selected values for the pK, standard molar enthalpy of reaction {Δ}rH , and standard molar heat-capacity change {Δ}rC p for the ionization reactions of 64 buffers many of which are relevant to biochemistry and to biology. The values pertain to the temperature T = 298.15 K and the pressure p = 0.1 MPa. The standard state is the hypothetical ideal solution of unit molality. These data permit one to calculate values of the pK and of {Δ}rH at temperatures in the vicinity (T=274K to 350K)} of the reference temperature δ= 298.15 K by using the following equations2.
CRC Handbook of Chemistry and Physics, 83rd Edition
83 Ed.
Publisher Info
CRC Press, Boca Raton, FL


buffers, enthalpy, equilibrium constant, evaluated data, Gibbs free energy, heat capacity, ionization, pK


Goldberg, R. , Kishore, N. and Lennen, R. (2002), Thermodynamic Quantities for the Ionization Reactions of Buffers in Water, CRC Press, Boca Raton, FL (Accessed July 23, 2024)


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Created December 1, 2002, Updated June 2, 2021