A 5.27-g sample of an ant-control preparation was decomposed by wet ashing with H₂SO4 and HNO3. The arsenic in une residue was reduced to the trivalent state with hydrazine. After the excess reducing agent had been removed, the arsenic(III) was oxidized with electrolytically generated 12 in a faintly alkaline medium: HASO + 1₂ + 2HCO HASO + 2 + 2CO + H₂O The titration was complete after a constant current of 105.2 mA had been passed for 10 min and 43 s. Express the results of this analysis in terms of the percentage As2O3 in the original sample.

A 5.27-g sample of an ant-control preparation was decomposed by wet ashing with H₂SO4 and HNO3. The arsenic in une residue was reduced to the trivalent state with hydrazine. After the excess reducing agent had been removed, the arsenic(III) was oxidized with electrolytically generated 12 in a faintly alkaline medium: HASO + 1₂ + 2HCO HASO + 2 + 2CO + H₂O The titration was complete after a constant current of 105.2 mA had been passed for 10 min and 43 s. Express the results of this analysis in terms of the percentage As2O3 in the original sample.

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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