Studies on Stability Constants of Salicylates Derivatives (Part-II)

The Job s method of continuous variation has been used to study the chelating behaviour of salicylates. In this regard. spectrophotometric measurement for 2-hydroxy-5-sulphobenzoic acid and 2-hydroxy 3-5, dinitrobenzoic acid, with (I) and (II) metals were made. The stability constants were calculated for above two systems. It is inferenced from this study that stability of chelates is governed by pH, constituent groups attached to 2-hydroxybenzoic acid. Therefore, it is concluded that the stability of chelates decreased with decrease pH and the presence of electron with drawing constituents groups (sulfo, dinitro group) also destabilize chelating system.