10. The following buffered solutions of weak acid (FHA spectrophotometrically in 2.00 cm cells 1.00 x 10-3 M) are measured %3D pH 7 8 19 10 11 0.000 0.163 0.750 1.172 1.240 1.250 1.250 Calculate Ka for the weak acid. Hint: start by identifying the absorbing form of the weak acid equilibrium, use the absorbance measurement to determine its as a function of pH and use the resulting line to concentration, plot log ( determine pKa• (HA)

10. The following buffered solutions of weak acid (FHA spectrophotometrically in 2.00 cm cells 1.00 x 10-3 M) are measured %3D pH 7 8 19 10 11 0.000 0.163 0.750 1.172 1.240 1.250 1.250 Calculate Ka for the weak acid. Hint: start by identifying the absorbing form of the weak acid equilibrium, use the absorbance measurement to determine its as a function of pH and use the resulting line to concentration, plot log ( determine pKa• (HA)

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter31: Introduction To Analytical Separations

Section: Chapter Questions

Problem 31.26QAP

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As pH changes, ho will absorbance change t the wavelength of the isosbestic point?
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