FUW TRENDS IN SCIENCE & TECHNOLOGY JOURNAL
(A Peer Review Journal)
e–ISSN: 2408–5162; p–ISSN: 2048–5170
keywords: Metal-ligand, pH-metric, stability constant, thermodynamic studies, benzimidazole
Metal-ligand complexations in solution of the transition metals with azole based ligands (triazole and benzimidazoleligand) in water-methanol medium by pH-metric titration with the glass electrode; ionic strength 0.1M KNO3 and buffer solutions at pH 7 and 9 were carried out. Titration were carried out for the ligand against 0.05M NaOH solution as wellason metal complexes (metal ligand) at various temperatures 35, 45 and 55oC. The pKa values (stability constants) were determined at the respective temperatures and found to decrease as the temperature increased. The results of thermodynamic studieshave revealed that themetal complexes were exothermically favourable while the negative Gibb’s free energy explained the spontaneity of the metal-ligand system and that the metals complexes were feasible at the respective temperatures.
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