11. A solution of 0.0500M Ca²* and 0.00500M Mg* was titrated against EDTA at pH = 10 (K'r for CaY2 =1.75 x 1010 and K't for MgY2 1.72 x 10). Which statement is NOT TRUE? a. The reaction of formation of the calcium complex ion occurs with lower tendency. b. In the titration curve of Mg*, a smaller change of pM occurs around the equivalence point. c. Eriochrome black T indicator could be used for both titrations. d. The pCa is larger than pMg after the excess addition of the EDTA.

11. A solution of 0.0500M Ca²* and 0.00500M Mg* was titrated against EDTA at pH = 10 (K'r for CaY2 =1.75 x 1010 and K't for MgY2 1.72 x 10). Which statement is NOT TRUE? a. The reaction of formation of the calcium complex ion occurs with lower tendency. b. In the titration curve of Mg*, a smaller change of pM occurs around the equivalence point. c. Eriochrome black T indicator could be used for both titrations. d. The pCa is larger than pMg after the excess addition of the EDTA.

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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EXAMPLE: Chromium(III) is slow to react with EDTA (H4Y) and is therefore determined by back-titration. A pharmaceutical preparation containing chromium(III) is analyzed by treating a 2.63g sample with 5mL of (0.0103M) EDTA. Following reaction, the unreacted EDTA is back-titrated with 1.32mL of (0.0112M) zinc solution. What is the percent chromium chloride in the pharmaceutical preparation?