Ionization constants of weak acids and bases in organic solvents

被引：144

作者：

Sarmini, K ^{[1
]}

Kenndler, E ^{[1
]}

机构：

[1] Univ Vienna, Inst Analyt Chem, A-1090 Vienna, Austria

来源：

JOURNAL OF BIOCHEMICAL AND BIOPHYSICAL METHODS | 1999年 / 38卷 / 02期

关键词：

organic solvents; pK(a); values; enthalpy/entropy; ionization; electrostatic effects; solute-solvent interactions;

D O I：

10.1016/S0165-022X(98)00033-5

中图分类号：

Q5 [生物化学];

学科分类号：

071010 ; 081704 ;

摘要：

A discussion of the influence of organic solvents on pK(a) values is presented. Enthalpy and entropy of ionization in organic solvents are compared with aqueous systems. The impact of the solvent on the ionization constants is interpreted based on the free energy of transfer applied to all particles involved in the ionization reaction of acids and bases, and the concept of the 'medium effect' on these species. The limitation of Born's approach (which takes into account only electrostatic effects on the ionization equilibrium) is demonstrated and the importance of solute-solvent interactions on the change of the pK(a) values emphasized. (C) 1999 Elsevier Science B.V. All rights reserved.

引用

页码：123 / 137

页数：15

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[2]

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