Use of complexones in chemical analysis. XIII. Potentiometric determination of certain cations by means of Complexone III solutions

Chelometric Titrations of Metal Ions with Potentiometric End Point Detection

“…I n the EDTA titration of this metal, the mercury electrode functions simply as a redox indicator electrode (Y), because the redox systems Fe(III)/ F e (11) and Fe (111) Y/Fe (11) Y determine mainly the potential of the electrode. The use of a platinum electrode is then preferable and the titration may be carried out according to PIibil (6).…”

The Versene complexes

“…(5) Titration of an unbuffered, nearly neutral solution of the metal with tetrasodium versene, noting a large increase in pH at the equivalence point ( 14)-( 6) Potentiometric determinations at a platinum electrode, particularly for iron (15,16).…”

Use of Chelating Agents as Reagents in Titrimetric Analysis

“…In this case the potential change at the end point is a result of the formation of a very stable virtually undissociated chelate with one of the oxidation states of the metal. Pribil (7) obtained excellent results in titrating iron(III) with disodium dihydrogen ethylenediamine tetraacetate in an ammonium acetate buffer. The use of this method is dependent upon the availability of a suitable indicator electrode and the rapid formation of a stable metal chelate.…”