The amount of Fe (AW 55.85) in a 0.4891-g sample of an ore was determined by a redox titration with K2Cr2O7 (FW 294.20). The sample was dissolved in HCl and the iron brought into the +2 oxidation state using a Jones reductor. Titration to the diphenylamine sulfonic acid end point required 36.92 mL of 0.02153 M K2Cr2O7. Report the iron content of the ore as %w/w Fe2O3 (FW 159.70). 31.45 % 54.46 % 77.86 % 12.98 %

The amount of Fe (AW 55.85) in a 0.4891-g sample of an ore was determined by a redox titration with K2Cr2O7 (FW 294.20). The sample was dissolved in HCl and the iron brought into the +2 oxidation state using a Jones reductor. Titration to the diphenylamine sulfonic acid end point required 36.92 mL of 0.02153 M K2Cr2O7. Report the iron content of the ore as %w/w Fe2O3 (FW 159.70). 31.45 % 54.46 % 77.86 % 12.98 %

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.31QAP

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