4.25 g calcium hydroxide, Ca(OH)2 sample was dissolved in 100.0 mL 0.50 M hydrochloric acid. The excess acid is back titrated with 0.10 M sodium carbonate standard solution and required 38.25 mL to reach the end point. a) Distinguish between a direct titration and a back titration. b) Write all the balanced chemical equations for the above reactions. c) Calculate the percentage purity of Ca(OH)2 in the sample. d) Choose one suitable indicator that can be used in the back titration to detect the end point. e) Give a reason of back titration is used in the above determination. f) Determine the pH of the excess acid before the back titration begins.

4.25 g calcium hydroxide, Ca(OH)2 sample was dissolved in 100.0 mL 0.50 M hydrochloric acid. The excess acid is back titrated with 0.10 M sodium carbonate standard solution and required 38.25 mL to reach the end point. a) Distinguish between a direct titration and a back titration. b) Write all the balanced chemical equations for the above reactions. c) Calculate the percentage purity of Ca(OH)2 in the sample. d) Choose one suitable indicator that can be used in the back titration to detect the end point. e) Give a reason of back titration is used in the above determination. f) Determine the pH of the excess acid before the back titration begins.

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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