Abstract
The purity of potassium dichromate was estimated by the coulometric titration using ferric sulfate as generating electrolyte and commercially available apparatus. The end point of titration was detected by the sensitive amperometric or potentiometric method. The coefficients of variation of these results were 0.016% and 0.068%, respectively. Potassium dichromate and potassium permanganate standard solutions were standardized by the same method in which the end point was detected by the sensitive amperometric method. The coefficients of variation of these results were 0.038% and 0.061%, respectively. Sodium arsenite standard solution was also standardized by the dead stop end point method using potassium iodide as generating electrolyte. The coefficient of variation of the results was 0.048%. Sources of the errors have been also discussed.
