A solution containing Mg2+ was buffered to pH 9.97 and titrated with EDTA. Eriochrome black T, with pKa1 = 6.3 and pKa2 = 11.6 was used as the indicator. It %3D is a diprotic acid, H2E What is the fraction of the predominant form of eriochrome black T in solution at this pH? (To answer this, report the alpha fraction of the indicator's most prevalent species at this pH) Review text sections 10.4 and 10.5 for help with this!

A solution containing Mg2+ was buffered to pH 9.97 and titrated with EDTA. Eriochrome black T, with pKa1 = 6.3 and pKa2 = 11.6 was used as the indicator. It %3D is a diprotic acid, H2E What is the fraction of the predominant form of eriochrome black T in solution at this pH? (To answer this, report the alpha fraction of the indicator's most prevalent species at this pH) Review text sections 10.4 and 10.5 for help with this!

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.20QAP

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A solution containing Mg2+ was buffered to pH 9.81 and titrated with EDTA. Eriochrome black T, with p?a1 = 6.3 and p?a2 = 11.6 was used as the indicator. It is a diprotic acid, H2E What is the fraction of the predominant form of eriochrome black T in solution at this pH? (To answer this, report the alpha fraction of the indicator’s most prevalent species at this pH)
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