An acid-base indicator, HIn, dissociates according to the reaction shown in an aqueous solution. Ka, Hin HIn(aq) In (aq) + H+(aq) The protonated form of the indicator, HIn, has a molar absorptivity of 3199 M-1 cm-1 and the deprotonated form, In¯, has a molar absorptivity of 21910 M-1 cm at 440 nm. The pH of a solution containing a mixture of HIn and In is adjusted to 6.21. The total concentration of HIn and In is 0.000124 M. The absorbance of this solution was measured at 440 nm in a 1.00 cm cuvet and was determined to be 0.882. Calculate pK for HIn. pka, Hin

An acid-base indicator, HIn, dissociates according to the reaction shown in an aqueous solution. Ka, Hin HIn(aq) In (aq) + H+(aq) The protonated form of the indicator, HIn, has a molar absorptivity of 3199 M-1 cm-1 and the deprotonated form, In¯, has a molar absorptivity of 21910 M-1 cm at 440 nm. The pH of a solution containing a mixture of HIn and In is adjusted to 6.21. The total concentration of HIn and In is 0.000124 M. The absorbance of this solution was measured at 440 nm in a 1.00 cm cuvet and was determined to be 0.882. Calculate pK for HIn. pka, Hin

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter15: Equilibria Of Other Reaction Classes

Section: Chapter Questions

Problem 82E: The simplest amino acid is glycine, H2NCH2CO2H. The common feature of amino acids is that they...

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