Komplexone XXV. Die polarographische Untersuchung von Austauschgleichgewichten. Neue Daten der Bildungskonstanten von Metallkomplexen der Äthylendiamin‐tetraessigsäure und der 1,2‐Diaminocyclohexan‐tetraessigsäure

Abstract The polarograms of the metal complexes of Ethylenediaminetetraacetic Acid and of 1,2‐Diaminocyclohexane‐tetraacetic Acid are described. In a mixture, containing the metal complex MY v −4 as well as the uncomplexed cation M + v , it is usually possible to determine the concentration of the latter with high accuracy with the aid of a polarograph. Such measurements have been used for the determination of the ratios of the formation constants of the complexes of two metals M and M′, and from these ratios the individual formation constants of 49 complexes have been obtained. The best values of the formation constants (20°, μ = 0,1) of metal complexes are tabulated.