The Reaction of Potassium Permanganate with Potassium Ferrocyanide and Some Binary Mixtures in Presence of Fluoride Ions

Department of Chemistry, Faculty of Science, Zagazig University, Benha, A. R. Egypt

Manuscript received 28 January 1982, accepted 7 June 1982

The reactions of potassium permanganate with potassium ferrocyanide and binary mixtures of ferrous-mercurous (1), ferrocyanide-mercurous(2) and ferrous-ferrocy­anide (3) have been studied potentiometrically in acid medium containing fluoride ions. For potassium ferrocyanide, good results are obtained at 0.018-1.8 N H₂,SO₄ in presence of 0.238-0.357 M NaF at temperature range 25-50°. But in the case of the mixtures, the optimum acidities are 0.315 N H₂,SO₄ (2, 3) and 0.22 N(1) in presence of 0.357 M NaF at 25°. 125-503 mg of ferrocyanide can be determined with high accuracy. The constituents of the mixtures can be titrated in presence of each other. The difficulty of precipitation of manganese(II) ferrocyanide can be overcome by keeping the reduction product of KMnO₄ as complex Mn(III) fluoride.