Komplexone XLIV. Die Komplexe der Anionen der Triäthylentetraminhexa‐Essigsäure mit Calcium(II), Kupfer(II) und Zink(II)

Using pH‐methods ‐ direct titration according to Schwarzenbach , and ligand‐ligand exchange ‐ the stability constants of the complexes of divalent calcium, copper and zinc ions with the anions of triethylenetetramine hexaacetic acid have been determined. The complications arising by the interpretation of the experimental measurements of pH‐values below 3.5 are discussed. These factors are normally not taken into account, and often wrong values of the equilibrium constants have been communicated.