A 0.5962 g sample of iron ore is dissolved in perchloric acid (HCIO4). All iron present is oxidized to Fe3*. The solution is filtered to remove solid matrix materials and made basic with addition of ammonium hydroxide. The iron precipitates as the Fe(OH)3.XH2O gel. The precipitate is collected in a cistern crucible and ignited to produce Fe203. What is the wt. % of iron in the sample if the analysis produced 0.3210 g Fe2O3? Fe3+ + 3 OH → Fe,O3 + → Fe203 H2 18.83% 9.415% 56.49% O 37.66%

A 0.5962 g sample of iron ore is dissolved in perchloric acid (HCIO4). All iron present is oxidized to Fe3*. The solution is filtered to remove solid matrix materials and made basic with addition of ammonium hydroxide. The iron precipitates as the Fe(OH)3.XH2O gel. The precipitate is collected in a cistern crucible and ignited to produce Fe203. What is the wt. % of iron in the sample if the analysis produced 0.3210 g Fe2O3? Fe3+ + 3 OH → Fe,O3 + → Fe203 H2 18.83% 9.415% 56.49% O 37.66%

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.27QAP

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