3+ 2+ 12-B. A 25.00-mL sample containing Fet and Cut required 16.06 mL of 0.050 83 M EDTA for complete titration. A 50.00-mL sample was treated with NH,F to bind Fet. Then Cu²+ was reduced and masked by thiourea. Addition of 25.00 mL of 0.050 83 M EDTA liberated Fe+ from its fluoride complex to form an EDTA complex. The excess EDTA 2+ required 19.77 mL of 0.018 83 M Pb²† to reach a xylenol orange end point. Find [Cu´“] in the unknown.

3+ 2+ 12-B. A 25.00-mL sample containing Fet and Cut required 16.06 mL of 0.050 83 M EDTA for complete titration. A 50.00-mL sample was treated with NH,F to bind Fet. Then Cu²+ was reduced and masked by thiourea. Addition of 25.00 mL of 0.050 83 M EDTA liberated Fe+ from its fluoride complex to form an EDTA complex. The excess EDTA 2+ required 19.77 mL of 0.018 83 M Pb²† to reach a xylenol orange end point. Find [Cu´“] in the unknown.

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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