Original scientific paper

Ionophoretic Technique for the Determination of Stability Constants of Mixed Complexes (M-Nitrilotriacetate-5-Amino Pentanoate Systems)

M. Vyas ; Electrochemical Laboratories, Department of Chemistry, University of Allahabad, Allahabad-211002, India
S. Singh ; Electrochemical Laboratories, Department of Chemistry, University of Allahabad, Allahabad-211002, India
S. R. Tripathi ; Electrochemical Laboratories, Department of Chemistry, University of Allahabad, Allahabad-211002, India
K. L. Yadava ; Electrochemical Laboratories, Department of Chemistry, University of Allahabad, Allahabad-211002, India

Abstract

A new method, involving the use of paper electrophoresis is described for the study of the equilibria in mixed ligand complex systems in solution. This technique is based on the movement of a spot of metal ion under an electric field with the complexants added in the background electrolyte at p'H = 8.5. Concentration of the primary ligand (NTA) was kept constant while that of the secondary ligand (5-amino pentanoic acid) was varied. The plots of-log [5-amino pentanoic acid] against mobility were used to obtain information on the forma tion of mixed complex and to calculate its stability constants. The binary equilibria M(II)-(5- amino pentanoic acid) and M(II)-NTA have also been studied since this is a prerequisite for the investigation of mixed complexes. The stability constants of the cornplexes, metal-nitrilotriacetate- 5-amino pentanoate have been found to be 5.85, 5.50, 5.22, 3.96 and 3.90 (log K values) for Cu(II), UOz(II), Ni(II), Co(II) and Zn(II) complexes, respectively, at fL = 0.1 mol/L and a temperature of 35 -c.

Keywords

Hrčak ID:

177276

URI

https://hrcak.srce.hr/177276

Publication date:

5.11.1986.

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