To adjust the thiosulfate (S2O3) solution to be used as a titrant in the copper determination, excess KI was added to exactly 25.0 mL of 5.68 x 103 M KIO3 solution to liberate iodine (12) and 16.4 mL of thiosulfate solution is being consumed in the titration of I2. In this standardization process, the concentration of the thiosulfate solution is calculated. 103 +51 (excess)+ 6H*→ 31z+ 3H2O Iz+ 2S2032→ S402²-+21 Then, for copper determination 25.0 mL of 250 mL copper-aliquots is taken and treated with excess KI. Cu²++ 21 (excess)→ Cul + % l2 The liberated l2 was titrated with the 8.2 mL of adjusted thiosulfate solution (S2O32-). I2+ 2S2032> S4O,²+21- Calculate, how many milligrams of copper is found in the sample? (Cu: 63.5 g/ mol)

To adjust the thiosulfate (S2O3) solution to be used as a titrant in the copper determination, excess KI was added to exactly 25.0 mL of 5.68 x 103 M KIO3 solution to liberate iodine (12) and 16.4 mL of thiosulfate solution is being consumed in the titration of I2. In this standardization process, the concentration of the thiosulfate solution is calculated. 103 +51 (excess)+ 6H*→ 31z+ 3H2O Iz+ 2S2032→ S402²-+21 Then, for copper determination 25.0 mL of 250 mL copper-aliquots is taken and treated with excess KI. Cu²++ 21 (excess)→ Cul + % l2 The liberated l2 was titrated with the 8.2 mL of adjusted thiosulfate solution (S2O32-). I2+ 2S2032> S4O,²+21- Calculate, how many milligrams of copper is found in the sample? (Cu: 63.5 g/ mol)

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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