Abstract
Stability constants and complex formation equilibria between Co(II) and sulfanilamide (SM) with dicarboxylic acids (L) were studied pH-metrically at 25 +/- 0.1 degrees C and ionic strength I= 0.1 mol/L NaClO4 in aqueous solutions. The stepwise method is responsible for the formation of [Co(II)-SM-L] complexes, while dicarboxylic acid ligation follows sulphanilamide-Co(II) binding. Stability constants were obtained by applying the potentiometric data in HYPERQUAD computer program. The stoichiometry of the formed complexes was confirmed by conductometric method. A comparison between binary and ternary complexes' relative stabilities was conducted.