A small amount of Mg-EDTA is often added in the titrimetric determination of water hardness. Why? A. Mg forms the most stable EDTA complex of all multivalent cations. B. It ensures that enough Mg ions are present for satisfactory indicator action. C. Mg-EDTA is inert and therefore does not influence the results, but it enhances indicator action. D. The Mg-EDTA dissociates after all the other cations have been titrated and therefore ensures that the end point is clearly visible.

A small amount of Mg-EDTA is often added in the titrimetric determination of water hardness. Why? A. Mg forms the most stable EDTA complex of all multivalent cations. B. It ensures that enough Mg ions are present for satisfactory indicator action. C. Mg-EDTA is inert and therefore does not influence the results, but it enhances indicator action. D. The Mg-EDTA dissociates after all the other cations have been titrated and therefore ensures that the end point is clearly visible.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.12QAP

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