A 1.0 g sample containing urea was dissolved in water and diluted in a 100.00 mL volumetric flask. 20.00 mL aliquot was mixed with 30.00 mL water and subjected to digestion with concentrated H2SO4. The ammonia produced is collected in 30.00 mL of 0.0500 M HCI and the excess acid is back titrated with 0.0500 M NAOH, requiring 6.80 mL. Calculate the weight percent urea [(NH2)2CO, FW=60.06 g/mol] in the sample.

A 1.0 g sample containing urea was dissolved in water and diluted in a 100.00 mL volumetric flask. 20.00 mL aliquot was mixed with 30.00 mL water and subjected to digestion with concentrated H2SO4. The ammonia produced is collected in 30.00 mL of 0.0500 M HCI and the excess acid is back titrated with 0.0500 M NAOH, requiring 6.80 mL. Calculate the weight percent urea [(NH2)2CO, FW=60.06 g/mol] in the sample.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.22QAP

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