4 Only 3. A 0.3246 g sample that might contain NaOH, Na₂CO,, NaHCO, or a permissiblemixture of the bases is titrated with 0.0828 M HCl by the double-indicatormethod. It is found that 30.38 ml of the acid are required to reach thephenolphthalein end point. Methyl orange is then added to the solution and thetitration continued using an additional of 7.83 ml of the acid. Calculate the % ofeach in the sample?4. The protein in a 1.2846-g sample of an oat cereal is determined by the Kjeldahlprocedure for organic nitrogen. The sample is digested with H₂SO4, the resultingsolution made basic with NaOH, and the NH, distilled into 50.00 mL of 0.09552 MHCI. The excess HCI is then back titrated using 37.84 mL of 0.05992 M NaOH.Given that the protein in grains averages 17.54% w/w N, report the % w/wprotein in the sample of cereal.

Problem based on volumetric analysis in which the titration of sample and a solution bis involved.…

4. The protein in a 1.2846-g sample of an oat cereal is determined by the Kjeldahl procedure for organic nitrogen. The sample is digested with H₂SO, the resulting solution made basic with NaOH, and the NH, distilled into 50.00 mL of 0.09552 M HCI. The excess HCI is then back titrated using 37.84 mL of 0.05992 M NaOH. Given that the protein in grains averages 17.54% w/w N, report the % w/w protein in the sample of cereal.

4. The protein in a 1.2846-g sample of an oat cereal is determined by the Kjeldahl procedure for organic nitrogen. The sample is digested with H₂SO, the resulting solution made basic with NaOH, and the NH, distilled into 50.00 mL of 0.09552 M HCI. The excess HCI is then back titrated using 37.84 mL of 0.05992 M NaOH. Given that the protein in grains averages 17.54% w/w N, report the % w/w protein in the sample of cereal.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter13: Titrations In Analytical Chemistry

Section: Chapter Questions

Problem 13.28QAP

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