The ethyl mercaptan concentration in a mixture was determined by shaking a 2.043-g sample with 50.00 mL of 0.01204 M 1₂ in a tightly stoppered flask: 2C₂H5SH + 12 C₂H5SSC₂H5 +21₂ + 2H+ The excess 1₂ was back-titrated with 18.23 mL of 0.01437 M Na2S2O3. Calculate the percentage of C₂H5SH (62.13 g/mol).

The ethyl mercaptan concentration in a mixture was determined by shaking a 2.043-g sample with 50.00 mL of 0.01204 M 1₂ in a tightly stoppered flask: 2C₂H5SH + 12 C₂H5SSC₂H5 +21₂ + 2H+ The excess 1₂ was back-titrated with 18.23 mL of 0.01437 M Na2S2O3. Calculate the percentage of C₂H5SH (62.13 g/mol).

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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The ethyl mercaptan (C2H5SH, 62.13 g/mol) concentration in a mixture was determined by shaking a 1.534 g sample with 50.0 mL of 0.01293 M I2 in a tightly stoppered flask: 2 C2H5SH (aq) + I2 (aq) --> C4H10S2 (aq) + 2 I- (aq) + 2 H+ (aq) The excess I2 was back-titrated with 15.72 mL of 0.01425 M Na2S2O3: I2 (aq) + 2 S2O32- (aq) --> 2 I- (aq) + S4O62- (aq) Calculate the percentage of ethyl mercaptan in the sample (3 sf)
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