Ascorbic acid (MW = 176.12 g/mole) is readily oxidized by molecular iodine in the presence of acid as shown in the reaction below: %3D CH2OH CH2OH снон снон H+ + 2 HI но он Once all of the ascorbic acid has reacted with the iodine, any excess iodine will react with a starch indicator to make a purple color, indicating the endpoint. This experiment will use an ascorbic acid solution of known concentration to determine the concentration of iodine. Once that concentration is known, it will be necessary to use that solution to determine the Vitamin C content of a commercial sample, such as orange or apple juice.

Ascorbic acid (MW = 176.12 g/mole) is readily oxidized by molecular iodine in the presence of acid as shown in the reaction below: %3D CH2OH CH2OH снон снон H+ + 2 HI но он Once all of the ascorbic acid has reacted with the iodine, any excess iodine will react with a starch indicator to make a purple color, indicating the endpoint. This experiment will use an ascorbic acid solution of known concentration to determine the concentration of iodine. Once that concentration is known, it will be necessary to use that solution to determine the Vitamin C content of a commercial sample, such as orange or apple juice.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter17: Electrochemistry

Section: Chapter Questions

Problem 80AP

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