.A sample of alfalfa meal weighing 2.0 g is analyzed by Kjeldahl method for the percentage of nitrogen. The liberated NH3 is caught in a solution of H3B03, and 8.23 ml of HCI are required in the subsequent titration. A sample of pure (NH4)2SO4 (132.12) weighing 0.61 g is treated with excess NaOH and the liberated NH3 (17.04) is also caught in H3BO3. The resulting solution requires 20 ml of the acid for titration. Calculate the percentage of protein in the sample using 6.25 as the factor.

.A sample of alfalfa meal weighing 2.0 g is analyzed by Kjeldahl method for the percentage of nitrogen. The liberated NH3 is caught in a solution of H3B03, and 8.23 ml of HCI are required in the subsequent titration. A sample of pure (NH4)2SO4 (132.12) weighing 0.61 g is treated with excess NaOH and the liberated NH3 (17.04) is also caught in H3BO3. The resulting solution requires 20 ml of the acid for titration. Calculate the percentage of protein in the sample using 6.25 as the factor.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter20: Applications Of Oxidation/reduction Titrations

Section: Chapter Questions

Problem 20.25QAP

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