9. A sodium thiosulfate solution is standardized using pure copper as the primary standard. A sample of copper weighing 0.2624 g is dissolved in acid, excess Kl is added, and the liberated iodine was titrated with 42.18 ml of sodium thiosulfate solution. Calculate the molarity of sodium thiosulfate solution. 2Cu2+ + 41 → 2Cul + l2 12 + 2S2032 → 21 + S4Og²-

9. A sodium thiosulfate solution is standardized using pure copper as the primary standard. A sample of copper weighing 0.2624 g is dissolved in acid, excess Kl is added, and the liberated iodine was titrated with 42.18 ml of sodium thiosulfate solution. Calculate the molarity of sodium thiosulfate solution. 2Cu2+ + 41 → 2Cul + l2 12 + 2S2032 → 21 + S4Og²-

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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A student was asked to determine the concentration of ammonia, a volatile substance, in a commercially available cloudy ammonia solution used for cleaning. First the student pipetted 25.00 mL of the cloudy ammonia solution into a 250.0 mL conical flask. 50.00 mL of 0.100 mol L-¹ HCl(aq) was immed added to the conical flask which reactedwith the ammonia in solution. The excess (unreacted) HC1 was then titrated with 21.50 mL 0. 050 M Na2CO3 (aq). Calculate the concentration of the ammonia in the cloudy ammonia solution.
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