A solution of Cu* is undergoing a redox titration by the addition of Ce*. The standard reduction half-reactions and potentialsare given.Ce* +e= Ce*E = +1.72 VCu+ + e CuE = +0.161 VThe table shows the properties of four redox indicators.ColorIndicatorOxidizedReduced E" (V)5,6-dimethylphenanthroline (Fe complex)indigotrisulfonic acidyellow-greenred+0.97bluecolorless+0.33phenosafranineredcolorless+0.28viologencolorlessblue-0.43Select a suitable indicator to observe the end point.viologenindigotrisulfonic acid5,6-dimethylphenanthroline (Fe complex)phenosafranineWhich color change would you observe at the end point?red to colorlessred to yellow-greenyellow-green to redblue to colorlesscolorless to bluecolorless to red

Given, Ce4++e-⇌Ce3+ E°=+1.72VCu2++e-⇌Cu+ E°=+0.161 V

A solution of Cu* is undergoing a redox titration by the addition of Ce**. The standard reduction half-reactions and potentials are given. Ce* +e=Ce* E = +1.72 V Cu2+ +e Cu* E = +0.161 V The table shows the properties of four redox indicators. Color Indicator Oxidized Reduced E" (V) yellow-green 5,6-dimethylphenanthroline (Fe complex) indigotrisulfonic acid phenosafranine red +0.97 blue colorless +0.33 red colorless +0.28 viologen colorless blue -0.43 Select a suitable indicator to observe the end point. viologen indigotrisulfonic acid 5,6-dimethylphenanthroline (Fe complex) phenosafranine Which color change would you observe at the end point? red to colorless red to yellow-green yellow-green to red blue to colorless

A solution of Cu* is undergoing a redox titration by the addition of Ce**. The standard reduction half-reactions and potentials are given. Ce* +e=Ce* E = +1.72 V Cu2+ +e Cu* E = +0.161 V The table shows the properties of four redox indicators. Color Indicator Oxidized Reduced E" (V) yellow-green 5,6-dimethylphenanthroline (Fe complex) indigotrisulfonic acid phenosafranine red +0.97 blue colorless +0.33 red colorless +0.28 viologen colorless blue -0.43 Select a suitable indicator to observe the end point. viologen indigotrisulfonic acid 5,6-dimethylphenanthroline (Fe complex) phenosafranine Which color change would you observe at the end point? red to colorless red to yellow-green yellow-green to red blue to colorless

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter21: Potentiometry

Section: Chapter Questions

Problem 21.26QAP

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