A 0.8965g ore sample is dissolved in nitric acid and then filtered. The aluminum is present in solution as AP. The solution is made basic with ammonium hydroxide, NH.OH, and the aluminum hydroxide, Al(OH): (FW 78.004), precipitates. This gel is filtered in a porous glass crucible, rinsed with dilute ammonium hydroxide, ignited, cooled in a desiccator, and weighed. The resulting alumina, Al:O; (FW 101.94), weighed 0.1605 g. Why is the solution filtered after acid dissolution? Why rinse with ammonium hydroxide sohution? What chemical transformation takes place during ignition? (Show the balanced chemical equation) Why use a desiccator during cooling? Calculate the weight percent Al (AW 26.9815) in the sample. Al(OH), -> Al:O, + H;o

A 0.8965g ore sample is dissolved in nitric acid and then filtered. The aluminum is present in solution as AP. The solution is made basic with ammonium hydroxide, NH.OH, and the aluminum hydroxide, Al(OH): (FW 78.004), precipitates. This gel is filtered in a porous glass crucible, rinsed with dilute ammonium hydroxide, ignited, cooled in a desiccator, and weighed. The resulting alumina, Al:O; (FW 101.94), weighed 0.1605 g. Why is the solution filtered after acid dissolution? Why rinse with ammonium hydroxide sohution? What chemical transformation takes place during ignition? (Show the balanced chemical equation) Why use a desiccator during cooling? Calculate the weight percent Al (AW 26.9815) in the sample. Al(OH), -> Al:O, + H;o

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter12: Gravimetric Methods Of Analysis

Section: Chapter Questions

Problem 12.25QAP

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