A quantitative analysis for ethanol, C2H60, is accomplished by a redox back titration. Ethanol is oxidized to acetic acid, C2H402, using excess dichromate, Cr207 2-, which is reduced to Cr3+. The excess dichromate is titrated with Fe2+, giving Cr3+ and Fe3+ as products. In a typical analysis, a 5.00-mL sample of a brandy is diluted to 500 mL in a volumetric flask. A 10.00-mL sample is taken and the ethanol is removed by distillation and collected in 50.00 mL of an 2- acidified solution of 0.0200 M K2Cr207. Titration of the unreacted Cr207 requires 21.48 mL of 0.1014 M Fe2+. Calculate the %w/v ethanol in the brandy. Which is the titrant in this problem? O C2H4O2 O Fe2+ C2H60 Cr207 2-

A quantitative analysis for ethanol, C2H60, is accomplished by a redox back titration. Ethanol is oxidized to acetic acid, C2H402, using excess dichromate, Cr207 2-, which is reduced to Cr3+. The excess dichromate is titrated with Fe2+, giving Cr3+ and Fe3+ as products. In a typical analysis, a 5.00-mL sample of a brandy is diluted to 500 mL in a volumetric flask. A 10.00-mL sample is taken and the ethanol is removed by distillation and collected in 50.00 mL of an 2- acidified solution of 0.0200 M K2Cr207. Titration of the unreacted Cr207 requires 21.48 mL of 0.1014 M Fe2+. Calculate the %w/v ethanol in the brandy. Which is the titrant in this problem? O C2H4O2 O Fe2+ C2H60 Cr207 2-

Chemistry

9th Edition

ISBN:9781133611097

Author:Steven S. Zumdahl

Publisher:Steven S. Zumdahl

Chapter15: Acid-base Equilibria

Section: Chapter Questions

Problem 96AE: One method for determining the purity of aspirin (C9H8O4) is to hydrolyze it with NaOH solution and...

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