The potassium dichromate (K2Cr207, Mw = 294.2 g/mole) contained in a 1.3 g of impure sample was determined by reaction with an excess of KI to produce l2, followed by titration with thiosulfate (S2032-): Cr2072- + 14H* + 61 → 2Cr3+ + 7H20 + 312 12 + 2S2032- - 21- + S4062- If 43.83 mL of a 0.1199 M thiosulfate solution to react completely with the iodine produced by the reaction with potassium dichromate. What is the percentage of K2Cr207 contained in the original sample?

The potassium dichromate (K2Cr207, Mw = 294.2 g/mole) contained in a 1.3 g of impure sample was determined by reaction with an excess of KI to produce l2, followed by titration with thiosulfate (S2032-): Cr2072- + 14H* + 61 → 2Cr3+ + 7H20 + 312 12 + 2S2032- - 21- + S4062- If 43.83 mL of a 0.1199 M thiosulfate solution to react completely with the iodine produced by the reaction with potassium dichromate. What is the percentage of K2Cr207 contained in the original sample?

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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