Thyroxine, with structure shown below, was fused with sodium to produce a fusion solution. The resulting solution was filtered and combined with 0.1M AgNO3 which produced a yellowish-white precipitate. Isolating the precipitate and adding 2M NH3 showed that some of the precipitate dissolved. Your interpretations suggest that bromine is present in contrast to the structure. Which of the following best explains the false positive result? Do NH₂ thyroxine НО. The fusion solution was not boiled after the fusion process. OH O Potassium fluoride (KF) was not added to the fusion solution. O The sample formed carbonate precipitates because of alkaline conditions. O The sample was not reacted with enough sodium metal, causing too few iodide ions to be liberated. O The fusion solution was not acidified and boiled after the fusion process.

Thyroxine, with structure shown below, was fused with sodium to produce a fusion solution. The resulting solution was filtered and combined with 0.1M AgNO3 which produced a yellowish-white precipitate. Isolating the precipitate and adding 2M NH3 showed that some of the precipitate dissolved. Your interpretations suggest that bromine is present in contrast to the structure. Which of the following best explains the false positive result? Do NH₂ thyroxine НО. The fusion solution was not boiled after the fusion process. OH O Potassium fluoride (KF) was not added to the fusion solution. O The sample formed carbonate precipitates because of alkaline conditions. O The sample was not reacted with enough sodium metal, causing too few iodide ions to be liberated. O The fusion solution was not acidified and boiled after the fusion process.

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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