Determination of fluoride with thorium nitrate by catalytic titration.
Amperometry, constant-current potentiometry and spectrophotometry were used to follow the course of catalytic titrations of fluoride and silicofluoride with thorium nitrate. The hydrogen peroxide-iodide system was used as the indicator reaction. Titrations were performed in 50% ethanolic acetate buffer, pH 3.6. Amounts of 3.70-6.85 mg of ammonium fluoride, 5.53-10.79 mg of potassium fluoride and 4.34-8.41 mg of sodium silicofluoride were determined with a maximum average deviation of 0.9%. The results obtained are in good agreement with those of comparable methods.
Gaál
F F
FF
Faculty of Sciences, Institute of Chemistry, University of Novi Sad, V. Vlahovića 2, YU-21000 Novi Sad, Yugoslavia.
Abramović
B F
BF
Canić
V D
VD