Interaction between hexacyanoferrate(<scp>II</scp>) ion and mercury(<scp>II</scp>) and silver(<scp>I</scp>) ions

Abstract

The interaction between hexacyanoferrate(II) ion and mercury(II) or silver(I) ion was studied conductometrically in aqueous solution. The maximum decrease in conductivity occurred at a 1 : 2 mole ratio of K4[Fe(CN)6] : HgCl2 or at a ca. 1 : 4 mole ratio of K4[Fe(CN)6] : AgNO3. The decrease in conductivity is considered to be due to complex formation between hexacyanoferrate(II) ion and the metal ions. The salt effect on the HgII-catalysed dissociation of [Fe(CN)6]4– to [Fe(CN)5H2O]3– is positive at low, but negative at high, ionic strength. The mechanism of this reaction is discussed.