Re-examination of the Kirkwood–Westheimer theory of electrostatic effects. III. Dissociation constants of cis-3- and trans-4-substituted cyclohexanecarboxylic acids in water–dimethyl sulfoxide mixtures

1978 ◽  
Vol 56 (8) ◽  
pp. 1130-1133 ◽  
Author(s):  
Jitka Kirchnerova ◽  
Patrick G. Farrell ◽  
John T. Edward ◽  
Jean-Claude Halle ◽  
Robert Schaal
Keyword(s):  
Dimethyl Sulfoxide ◽  
Dissociation Constant ◽  
Dissociation Constants ◽  
Solvent Composition ◽  
Potentiometric Method ◽  
Acid Dissociation ◽  
Electrostatic Effects ◽  
Acid Dissociation Constants ◽  
Cyclohexanecarboxylic Acid

Acid dissociation constants of two cis-3- and of four trans-4-substituted cyclohexanecarboxylic acids in water – dimethyl sulfoxide mixtures of varying composition were determined by a potentiometric method. Results have been analyzed according to the model of Kirkwood and Westheimer, and shown to differ from calculated values because of certain oversimplifications built into the model. Dissociation constant differences between cyclohexanecarboxylic acid and the compounds studied vary only slightly with changing solvent composition.

Influence du substituant tertiobutyl-4 sur les constantes d'acidité du cation cyclohexylammonium et de l'acide cyclohexane carboxylique dans les milieux mixtes eau–DMSO et méthanol–DMSO

1976 ◽  
Vol 54 (12) ◽  
pp. 1899-1905 ◽  
Author(s):  
John T. Edward ◽  
Patrick G. Farrell ◽  
Jitka Kirchnerova ◽  
Jean-Claude Halle ◽  
Robert Schaal
Keyword(s):  
Dissociation Constants ◽  
Potentiometric Method ◽  
Acid Dissociation ◽  
Cyclohexane Ring ◽  
Acid Dissociation Constants ◽  
Tert Butyl ◽  
Butyl Group ◽  
Tert Butyl Group ◽  
Solvent Molecules

Acid dissociation constants for the compounds 1–6 in water–DMSO and methanol–DMSO of varying composition have been determined by a potentiometric method. In all solvents the equatorial group ionized more easily, by gain or loss of a proton, than the axial group, but in the more aqueous solvents the presence of a tert-butyl group across the cyclohexane ring inhibited this ionization slightly. An explanation based on displacement of solvent molecules from the outer solvation sphere is advanced.

scholarly journals Acid dissociation constants of tetracyanohydroxooxomolybdate(IV) ion

1973 ◽  
Vol 26 (3) ◽  
pp. 671 ◽  
Author(s):  
M Aijaz Beg ◽  
Kabir-ud-Din ◽  
RA Khan
Keyword(s):  
Hydrochloric Acid ◽  
Dissociation Constant ◽  
Titration Curve ◽  
Dissociation Constants ◽  
Acid Dissociation ◽  
Thermodynamic Quantities ◽  
Method Of Least Squares ◽  
Acid Dissociation Constants ◽  
Ph Titration ◽  
The Third

The third dissociation constant of tetracyanohydroxooxomolybdic acid, H3[MoO(OH)(CN)4], has been obtained in the temperature range 25-50�C from the pH-titration curve of its tripotassium salt against hydrochloric acid. The values of pK3 fitted an equation of Harned- Robinson type: �������������������� pK3 = (1730.72/T)-6.19+0.0308T) obtained by the method of least squares. ��� Thermodynamic quantities ΔG�, ΔH�, ΔS�, and ΔC�p for the process have been evaluated at 30�C.

THE SULPHURIC ACID SOLVENT SYSTEM: PART II. CONDUCTIVITY MEASUREMENTS ON SOLUTIONS OF SOME ACIDS

1961 ◽  
Vol 39 (6) ◽  
pp. 1266-1273 ◽  
Author(s):  
J. Barr ◽  
R. J. Gillespie ◽  
E. A. Robinson
Keyword(s):  
Dissociation Constant ◽  
Sulphuric Acid ◽  
Dissociation Constants ◽  
Solvent System ◽  
Acid Dissociation ◽  
Acid System ◽  
Conductivity Measurements ◽  
Acid Dissociation Constants ◽  
Strong Base ◽  
System Part

Conductivity measurements have been made on solutions of the following substances in sulphuric acid: HClO4, HSO3F, HSO3Cl, HPO2F2, HAs(HSO4)4, CH3SO3H, and CF3CO2H. Of these substances HSO3F, HSO3Cl, HAs(HSO4)4, and probably HClO4, behave as acids, CF3CO2H is a non-electrolyte, and HPO2F2, and probably CH3SO3H, are bases of the sulphuric acid system. Acid dissociation constants for HSO3F, HSO3Cl, and HAs(HSO4)4 have been determined by comparing the conductivities of their solutions with those of H2S2O7, whose dissociation constant is known from other measurements, and also by conductimetric titration with a strong base, e.g. KHSO4. These acids of the sulphuric acid system decrease in strength in the order HSO3F > HAs(HSO4)4 > HSO3Cl > HClO4.

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