When treated with a solution of ammonium sulfate an unknown solution produced heavy white precipitate. After centrifuging to remove the precipitate, the clear solution was treated with ammonium oxalate, (NH)2C204, and no precipitate formed. Further treatment of the clear solution with Na,HPO4 and NaOH produced a white precipitate which was isolated by centrifugation. This precipitate was then dissolved with a few drops of hy drochloric acid, a magnesium indicator solution was added, and the solution was made basic. Centrifugation gave a "blue lake". When a separate sample of the unknown solution was treated with sodium hydroxide, ammonia gas was produced which turned red litmus to blue. This unknown solution contained

When treated with a solution of ammonium sulfate an unknown solution produced heavy white precipitate. After centrifuging to remove the precipitate, the clear solution was treated with ammonium oxalate, (NH)2C204, and no precipitate formed. Further treatment of the clear solution with Na,HPO4 and NaOH produced a white precipitate which was isolated by centrifugation. This precipitate was then dissolved with a few drops of hy drochloric acid, a magnesium indicator solution was added, and the solution was made basic. Centrifugation gave a "blue lake". When a separate sample of the unknown solution was treated with sodium hydroxide, ammonia gas was produced which turned red litmus to blue. This unknown solution contained

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.33QAP

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