Potentiometric studies on the ternary systems beryllium-iminodiacetic acid-dicarboxylic or hydroxy acids

Chemical Laboratories, Agra College, Agra, India.

Abstract

Potentiometric evidences have been cited for the formation of Be(I l)-IMDA-H₂A/H₂A' [IMDA = iminodiacetic acid, H₂A = dicarboxylic acids (OX = oxalic acid, PHA = phthalic acid) or H₂A' = hydroxy acids (SA = salicylic acid, SSA = 5 - sulfosalicylic acid, HG = glycolic acid, MAND = mandelic acid)]. The formation constants (log KMLL') and free energies of formation (∆F°) have been calculated. The order of stability in terms of dicarboxylic acids (H₂A) and hydroxy acids (H₂A') has been found to be PHA > OX, SA > SSA and HG > MAND.

Résumé

Arguments polentiométriques pour la formation de Be(II)-IMDA-H₂A/H₂A' [IMDA = ac. iminodiacétique, H₂A = ac. dicarboxylique (OX = oxolique, PHA = phtalique), H₂A' = hydroxyacide (SA = salicyclique, SSA = sulfo- 5 salicylique, HG = glycolique, MAND = mandélique)]. Les constantes de formation (log K_MLL') et énergies libres de formation ∆F° ont été calculées. Les stabilités, pour les familles d’acides, se classent comme suit : PHA > OX, SA > SSA et HG > MAND.