EVALUATION OF DISSOCIATION AND THERMODYNAMIC CONSTANTS OF QUINOLINE USING POTENTIOMETRIC METHOD IN AQUEOUS AND MIXED 0RGANIC-WATER SOLVENTS

Authors

  • Hafiz A Bari Indher Center of Excellence in Analytical Chemistry, University of Sindh, Allama I I Kazi Campus, Jamshoro, Sindh, Pakistan
  • A W K Khanzada Center of Excellence in Analytical Chemistry, University of Sindh, Allama I I Kazi Campus, Jamshoro, Sindh, Pakistan

Keywords:

Dissociation constants, Potentiometry, Quinoline, Thermodynamic-parameters .

Abstract

The dissociation constant (pK,.) and thermodynamic parameters Gibb's free energies (G) of quinoline compound are determined by potentiometric pH titrations in aqueous solutions at 25 to 50°C and in various mixtures of water and organic solvent systems at 25°C ±  0. 1°c.

It is observed that the mixed ionization constant (pK,.M) and thermodynamic ionization constant (pK,T) values of quinoline decrease with the i ncrease of temperature and concentration of organic-water solvent systems. The curve is a parabolic one. These results are discussed in terms of solvent characteristics, solvent basicity and stabilization of conjugate acid for base by hydrogen bonding interaction in hydro-organic solvent media.

The values of dissociation constant are calculated by a computer programme written in GW-BASIC. From pK, values Gibb's free energies G for the respective pK, values are computed and discussed in terms of solute solvent interactions.

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Published

2001-02-19

How to Cite

Indher, H. A. B., & Khanzada, A. . W. K. (2001). EVALUATION OF DISSOCIATION AND THERMODYNAMIC CONSTANTS OF QUINOLINE USING POTENTIOMETRIC METHOD IN AQUEOUS AND MIXED 0RGANIC-WATER SOLVENTS. Biological Sciences - PJSIR, 44(1), 12–17. Retrieved from http://v2.pjsir.org/index.php/biological-sciences/article/view/1863

Issue

Vol. 44 No. 1 (2001): Pakistan Journal of Scientific and Industrial Research

Section

Articles