A POTENTIOMETRIC STUDY ON THE COMPLEXATION OF AG(I) WITH VARIOUS N-METHYL AND C-METHYL SUBSTITUTED ETHYLENEDIAMINES IN 1-M NO3-

The complexation of Ag(I) with five different N-methyl substituted, tw o C-methyl substituted ethylenediamines and ethylenediamine itself is studied using potentiometric pH and pAg measurements in 1 M KNO3 at 25 .0-degrees-C. Mononuclear complexes, polynuclear complexes and their p rotonated forms are detected and the respective stability constants ar e tabulated. The stability constant of a given species generally decre ases as the methylation increases on the terminal amino groups probabl y due to an increased steric hindrance. The number of species also dec reases as the methylation increases. The stability constants of the et hylenediamines are also compared with previously determined stability constants of Ag(I)-propylenediamine complexes and some relationships a re identified.