4. A 0.5843-g sample of a plant food preparation was analyzed for its N content by the Kjeldahl method, the liberated NH3 being collected in 50.00 mL of 0.1062 M HCI. The excess acid required an 11.89 mL back-titration with 0.0925 M NaOH. Express the results of this analysis in terms of: (a) %N (FW 14.007 g/mol). (b) %urea, H2NCONH2 (FW 60.06 g/mol). (c) %(NH4)2SO4 (FW 132.141 g/mol). (d) %(NH4):PO4 (FW 149.09 g/mol).

4. A 0.5843-g sample of a plant food preparation was analyzed for its N content by the Kjeldahl method, the liberated NH3 being collected in 50.00 mL of 0.1062 M HCI. The excess acid required an 11.89 mL back-titration with 0.0925 M NaOH. Express the results of this analysis in terms of: (a) %N (FW 14.007 g/mol). (b) %urea, H2NCONH2 (FW 60.06 g/mol). (c) %(NH4)2SO4 (FW 132.141 g/mol). (d) %(NH4):PO4 (FW 149.09 g/mol).

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.26QAP

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