Reaktion von Vanadium(IV) mit 3′-Pyridylfluoron und seine photometrische Bestimmung

The application of automatic titration instruments for volumetric determinations using catalytic indicator reactions is described. Examples for a photometric (Mn²⁺ with EDTA), potentiometric (Hg²⁺ and Ag⁺ with KI, I^? with Hg²⁺) and biamperometric (Cu²⁺ with EDTA) regulation of the automatic titrator are given. In some of these methods, contrary to the usual way, it is the inhibitor which serves as a titrant (“titration with the brake”) and not the catalyst.