A sodium thiosulfate solution can be standardized by using it to titrate the iodine liberated by the action of excess KI on a known weight of primary standard K2Cr2O7: Cr2O72- + 6I- + 14H+ → 2 Cr3+ + 3I2 + 7H2O I2 + 2S2O32- → 2I- + S4O62- Calculate the molar concentration of the sodium thiosulfate solution if 31.47 mL of this solution were required to titrate a sample prepared using 0.2177 g pure K2Cr2O7.

A sodium thiosulfate solution can be standardized by using it to titrate the iodine liberated by the action of excess KI on a known weight of primary standard K2Cr2O7: Cr2O72- + 6I- + 14H+ → 2 Cr3+ + 3I2 + 7H2O I2 + 2S2O32- → 2I- + S4O62- Calculate the molar concentration of the sodium thiosulfate solution if 31.47 mL of this solution were required to titrate a sample prepared using 0.2177 g pure K2Cr2O7.

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

Chapter11: Solutions

Section: Chapter Questions

Problem 72AP

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