Abstract
Equilibria between 2-hydroxynaphthylazoantipyrine and protons or bivalent transition metal ions have been investigated potentiometrically at 25±0. 1°C in 0.1 M NaNO
3
solutions. The experimental data were fitted assuming the formation of 1:1 and 1:2 complex species and their formation constants were calculated using the non-linear least square computer program MINIQUAD. The solid complexes of Cu(II), Co(II), Ni(II), UO
2
(VI) and Pd(II) have been prepared and characterized by elemental analyses, conductance, spectral and magnetic measurements. It has been found that 1:2 (metal: ligand) complexes were formed with Ni(II) and Co(II) and 1:1 complexes with Cu(II), Pd(II) and UO
2
(VI). Coordination seems to occur with the metal ion through the phenolic oxygen, carbonyl oxygen and azo nitrogen atoms.
Referee I: R. S. Pilato
Referee II: J. D. Ortego