The arsenic in a 1.208-g sample of a pesticide was converted to H3 AsO4 by suitable treatment. The acid was then neutralized, and 44.00 mL of 0.05854 M AgNO, was added to precipitate the arsenic quantitatively as Ag3 AsO4. The excess Ag* in the filtrate and in the washings from the precipitate was titrated with 9.69 mL of 0.1000 M KSCN, and the reaction was Ag+ + SCN¯ → AgSCN(s) Find the percentage of As2 O3 in the sample. Percentage of As2O3 =

The arsenic in a 1.208-g sample of a pesticide was converted to H3 AsO4 by suitable treatment. The acid was then neutralized, and 44.00 mL of 0.05854 M AgNO, was added to precipitate the arsenic quantitatively as Ag3 AsO4. The excess Ag* in the filtrate and in the washings from the precipitate was titrated with 9.69 mL of 0.1000 M KSCN, and the reaction was Ag+ + SCN¯ → AgSCN(s) Find the percentage of As2 O3 in the sample. Percentage of As2O3 =

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.22QAP

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A chemist dissolves a 1.497-g sample of a type of metal (an alloy of Sn, Pb, Sb, and Cu) in nitric acid, and metastannic acid, H2SnO3, is precipitated. She heats the precipitate to drive off the water, which leaves 0.4909 g of tin(IV) oxide. What was the percentage of [in in the original sample?
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A student was asked to determine the concentration of ammonia, a volatile substance, in a commercially available cloudy ammonia solution used for cleaning. First the student pipetted 25.00 mL of the cloudy ammonia solution into a 250.0 mL conical flask. 50.00 mL of 0.100 mol L-¹ HCl(aq) was immed added to the conical flask which reactedwith the ammonia in solution. The excess (unreacted) HC1 was then titrated with 21.50 mL 0. 050 M Na2CO3 (aq). Calculate the concentration of the ammonia in the cloudy ammonia solution.
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