6. Titration of Ca²+ and Mg2+ in a 50.00-mL hard water sample required 23.65 mL of 0.01205 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate Mg2+ as Mg(OH)2(s). The supernatant liquid was titrated with 14.53 mL of the EDTA solution. Calculate the total hardness of the water sample, expressed as ppm CaCO3.

6. Titration of Ca²+ and Mg2+ in a 50.00-mL hard water sample required 23.65 mL of 0.01205 M EDTA. A second 50.00-mL aliquot was made strongly basic with NaOH to precipitate Mg2+ as Mg(OH)2(s). The supernatant liquid was titrated with 14.53 mL of the EDTA solution. Calculate the total hardness of the water sample, expressed as ppm CaCO3.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter17: Complexation And Precipitation Reactions And Titrations

Section: Chapter Questions

Problem 17.35QAP

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