The total concentration of Ca²+ and Mg²+ in a sample of hard water was determined by titrating a 0.100-L sample of the water with a solution of EDTA. The EDTA chelates the two cations: Mg+ + [EDTA]+ Ca2+ + [EDTA]+ [Mg(EDTA)]²- [Ca(EDTA)]?- It requires 31.5 ml. of 0.0104 M[EDTA]* solution to reach the end point in the titration. A second 0.100-L sample was then treated with sulfate ion to precipitate Ca?+ as calcium sulfate. The Mg2+ was then titrated with 18.7 mL of 0.0104 M [EDTA]*. Calculate the concentrations of Mg²+ and Ca2 in the hard water in mg/L.

The total concentration of Ca²+ and Mg²+ in a sample of hard water was determined by titrating a 0.100-L sample of the water with a solution of EDTA. The EDTA chelates the two cations: Mg+ + [EDTA]+ Ca2+ + [EDTA]+ [Mg(EDTA)]²- [Ca(EDTA)]?- It requires 31.5 ml. of 0.0104 M[EDTA]* solution to reach the end point in the titration. A second 0.100-L sample was then treated with sulfate ion to precipitate Ca?+ as calcium sulfate. The Mg2+ was then titrated with 18.7 mL of 0.0104 M [EDTA]*. Calculate the concentrations of Mg²+ and Ca2 in the hard water in mg/L.

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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