An acid-base indicator, HIn, dissociates according to the following reaction in an aqueous solution. K. HIn(aq) = In (aq) + H* (aq) The protonated form of the indicator, HIn, has a molar absorptivity of 2777 M-1.cm-1 and the deprotonated form, In-, has a molar absorptivity of 19024 M-1.cm-1 at 440 nm. The pH of a solution containing a mixture of Hln and In- is adjusted to 5.86. The total concentration of HIn and In- is 0.000184 M. The absorbance of this solution was measured at 440 nm in a 1.00 cm cuvette and was determined to be 0.884. Calculate pka for HIn.

An acid-base indicator, HIn, dissociates according to the following reaction in an aqueous solution. K. HIn(aq) = In (aq) + H* (aq) The protonated form of the indicator, HIn, has a molar absorptivity of 2777 M-1.cm-1 and the deprotonated form, In-, has a molar absorptivity of 19024 M-1.cm-1 at 440 nm. The pH of a solution containing a mixture of Hln and In- is adjusted to 5.86. The total concentration of HIn and In- is 0.000184 M. The absorbance of this solution was measured at 440 nm in a 1.00 cm cuvette and was determined to be 0.884. Calculate pka for HIn.

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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