5. 0.1500 g sample of chromium ore was dissolved and the chromium oxidized to chromate ion. The solution was treated with 25.00 mL of 0.3500 M AGNO3. The resulting precipitate, from the reaction of the excess and analyte in 1: 1 mole relationship, Ag2CrO4 was removed and discarded. The excess AGNO3 required 30.50 mL of 0.200 M KSCN for titration in a 1:1 mole relationship. Calculate the % Cr2O3 in the ore if the mole relationship between Cr2O3 and CrO42- is 1:2 respectively.

5. 0.1500 g sample of chromium ore was dissolved and the chromium oxidized to chromate ion. The solution was treated with 25.00 mL of 0.3500 M AGNO3. The resulting precipitate, from the reaction of the excess and analyte in 1: 1 mole relationship, Ag2CrO4 was removed and discarded. The excess AGNO3 required 30.50 mL of 0.200 M KSCN for titration in a 1:1 mole relationship. Calculate the % Cr2O3 in the ore if the mole relationship between Cr2O3 and CrO42- is 1:2 respectively.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.34QAP

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