A 5.276 g sample of Al-Mg alloy is digested in nitric acid (to Al*3 and Mg*²). The solution is diluted to 500.00 mL and three 100.00 mL aliquots are treated with ammonia, the resulting Al(OH)3 precipitate is dried and then ignited to alumina, Al2O3 (MM = 101.961 g/mol). If the average mass of alumina obtained was 1.444 g, what was the percentage of aluminum (MM = 26.9815 g/mol) in the original sample?

A 5.276 g sample of Al-Mg alloy is digested in nitric acid (to Al3 and Mg²). The solution is diluted to 500.00 mL and three 100.00 mL aliquots are treated with ammonia, the resulting Al(OH)3 precipitate is dried and then ignited to alumina, Al2O3 (MM = 101.961 g/mol). If the average mass of alumina obtained was 1.444 g, what was the percentage of aluminum (MM = 26.9815 g/mol) in the original sample?

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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