5. A 0.9092 g sample of wheat flour was analysed by the Kjeldahl procedure. The ammonia formed was distilled into 50.00 mL of 0.02532 M H2SO4. A 7.46 mL back-titration of 0.04917 M NaOH was required. (Note the stoichiometry of your acid and base) Calculate the a. %N (FM=14.007) in the sample, b. %Protein in the sample (factor = 5.70)

5. A 0.9092 g sample of wheat flour was analysed by the Kjeldahl procedure. The ammonia formed was distilled into 50.00 mL of 0.02532 M H2SO4. A 7.46 mL back-titration of 0.04917 M NaOH was required. (Note the stoichiometry of your acid and base) Calculate the a. %N (FM=14.007) in the sample, b. %Protein in the sample (factor = 5.70)

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter10: Potentiometry And Redox Titrations

Section: Chapter Questions

Problem 8P

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A 0.1093-g sample of impure Na2CO3 was analyzed by the Volhard Method. After adding 50.00 mL of 0.06911 M AgNO3, the sample was back titrated with 0.05781 M KSCN, requiring 27.36 mL to reach the end point. Report the purity of Na2CO3 sample.
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A 0.9092 g sample of wheat flour was analysed by the Kjeldahl procedure. The ammoniaformed was distilled into 50.00 mL of 0.02532 M H2SO4. A 7.46 mL back-titration of 0.04917 MNaOH was required. (Note the stoichiometry of your acid and base) Calculate thea. %N (FM=14.007) in the sample,b. %Protein in the sample (factor = 5.70)
A 0.1093-g sample of impure Na2CO3 was analyzed by the Volhard method. After adding 50.00 mL of 0.06911 M AgNO3, the sample was back-titrated with 0.05781 M KSCN, requiring 27.36 mL to reach the endpoint. Report the purity of the Na2CO3 sample. [Ans. 90.9 % (w /w )]
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