A student was asked to determine the purity of sodium thiosulfate, Na2S2O3 sample by coulometric titration. Oxidation of thiosulfate involves one electron. Gerald prepared a 50 mL solution with 0.1132 g crude sample. A 10 mL aliquot was pipetted along with KI and phosphate buffer. Starch powder was used as indicator. Titration process took 221 seconds to achieve end point under constant current of 38.45 mA. Determine the purity of sodium thiosulfate (158.1 g/mol) crude sample. (F=96485 C/mol e

A student was asked to determine the purity of sodium thiosulfate, Na2S2O3 sample by coulometric titration. Oxidation of thiosulfate involves one electron. Gerald prepared a 50 mL solution with 0.1132 g crude sample. A 10 mL aliquot was pipetted along with KI and phosphate buffer. Starch powder was used as indicator. Titration process took 221 seconds to achieve end point under constant current of 38.45 mA. Determine the purity of sodium thiosulfate (158.1 g/mol) crude sample. (F=96485 C/mol e

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter22: Bulk Electrolysis: Electrogravimetry And Coulometry

Section: Chapter Questions

Problem 22.33QAP

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