Summary
Proton-ligand dissociation constant of 2-mercapto-5-(2-hydroxynaphthylideamino)-1,3,4-thiadiazole (MHT) and the stepwise stability constants of its metal complexes were determined potentiometrically in 40 mass/mass% ethanol-water mixture containing 0.1 M KCl. The stabilities of the complexes follow the order: Cu2+>Ni2+>Co2+>Mn2+. The dissociation constant (pKH) of MHT and the stability constants (logK) of its metal complexes were determined at different temperatures and the corresponding thermodynamic parameters were calculated and discussed. The proton dissociation process is non-spontaneous, endothermic and entropically unfavoured. The formation of the metal complexes was found to be spontaneous, endothermic and entropically favoured.
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Gaber, M., Al-Shihry, S. & El-Bindary, A. Potentiometric and thermodynamic studies of 2-mercapto-5-(2-hydroxynaphthylideamino)-1,3,4-thiadiazole and its metal complexes. J Therm Anal Calorim 82, 63–68 (2005). https://doi.org/10.1007/s10973-005-0842-z
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DOI: https://doi.org/10.1007/s10973-005-0842-z