Dissociation constants of organic acids

G. Kortiim, W. Vogel and K. Andrussow, Dissociation Constants of Organic Acids in Aqueous Solution, Butterworths, London, 1961. 

In recent years various attempts have been made to account for the observed differences between the dissociation constants of organic acids, whose molecules differ only slightly from each other. The proposed explanations have naturally been given in each case in terms of the structures of the respective neutral acid molecules.1 In the tentative discussion of HN03 and HI03 that has just been given, the approach has been quite different we focused attention, not on the neutral molecule or on the structure of the anion, but on the condition of the solvent in the vicinity of the anion. 

Kortum, G. Vogel, W. Andrussow, K. "Dissociation Constants of Organic Acids in Aqueous Solution" ... 

Dissociation Constants of Organic Acids in Aqueous Solution,... 

Values less than 3 and greater than 10 are approximate, and values at the extremes of the scale probably have only qualitative significance. Complications of pJf data may be found in D. D. Perrin, Dissociation Constants of Organic Bases in Aqueous Solution, Butterworths, London, 1965 G. Kortum, W. Vogel, and K. Andrussow, Dissociation Constants of Organic Acids in Aqueous Solution, Butterworths, London, 1961 and in Refs. 1, 5, 8, and 9. 

Kortiim G, Vogel W, Andrussow K (1961) Dissociation constants of organic acids in aqueous solution. Butterworths, London... 

Refs. [i] Todd JF (1991) Pure Appl Chem 63 1541 [ii] Dissociation constants of inorganic acids and bases. In Lide DR (ed) (2003) CRC handbook of chemistry and physics, 84th edn. CRCPress, Boca Raton, pp 8-44 - 8-45 [Hi] Dissociation constants of organic acids and bases. In Lide DR (ed) (2003) CRC handbook of chemistry and physics, 84tn edn. CRC... 

J This polarization along aliphatic chains forms the only explanation of the dissociation constants of organic acids, in particular of the effect of substituents, and must also, according to N. Bjerrum Zeitschr. f. phys. Chemie 106, 220 (1923)), be taken into account in the theoretical explanation of the dissociation constants of poly basic acids. Quantitative limits to the magnitude of this effect may be obtained by experimenting with different solvents (L. Ebert, Ber. d. dtsch. chem. Ges., 175 (1925)) for short chains its value is fgund to be considerable. 

Extensive experimental material for testing the anticipated effects is to be found in the dissociation constants of organic acids. It must be observed, however, that the dissociation constant as a constant of equilibrium is only to be regarded as a measure of the frequency... 

Kirkwood, J.J. and Westheimer, F.H. (1938). The Electrostatic Influence of Substituents on the Dissociation Constants of Organic Acids. I. J.Chem.Phys., 6,506-512. 

The literature on proton binding by humic substances indicates that statistical effects, delocalization effects, and, probably most importantly, the effects of dipolar groups on the acidity of a functional group have generally been ignored. An attempt has been made in this chapter to provide the reader with a rather detailed discussion of the nature of substituent effects on the dissociation constants of organic acids. Statistical, electrostatic, and delocalization effects have been treated separately. 

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