7. A sample of anhydrous NaHCO; (FM = 84.007) is suspected to be contaminated with either NaOH (FM = 39.997) or NazCO3 (FM = 105.989). To verify the suspicion, a 0.7483 g sample was dissolved to prepare a 50.00 mL solution, and a 10.00 mL aliquot was taken to prepare a 100 mL solution, where 25.00 mL was analyzed using double flask method. If the sample requires 0.45 mL of standard 0.0125 N HCI to reach the phenolphthalein endpoint and 35.95 mL to reach the bromcresol green endpoint, calculate the percentage composition (in %w/w) of all the basic components in the sample.

7. A sample of anhydrous NaHCO; (FM = 84.007) is suspected to be contaminated with either NaOH (FM = 39.997) or NazCO3 (FM = 105.989). To verify the suspicion, a 0.7483 g sample was dissolved to prepare a 50.00 mL solution, and a 10.00 mL aliquot was taken to prepare a 100 mL solution, where 25.00 mL was analyzed using double flask method. If the sample requires 0.45 mL of standard 0.0125 N HCI to reach the phenolphthalein endpoint and 35.95 mL to reach the bromcresol green endpoint, calculate the percentage composition (in %w/w) of all the basic components in the sample.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.40QAP

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