3. A solution is prepared by mixing 1.00 mmol of a weak acid (HA, pK2 = 6.44) with an unknown amount of KOH. The solution is diluted to 1.00 L using deionized water. An aliquot of the solution is placed in a 1.00-cm cuvet. The absorbance of the solution at 285 nm is 0.7748. Using the measured absorbance value, calculate the concentrations of HA and A in the solution. Then calculate the pH of the solution. You may assume all activity coefficients are equal to unity. НА A- 2050 Molar absorptivity at 285 nm (M² cm) 456

3. A solution is prepared by mixing 1.00 mmol of a weak acid (HA, pK2 = 6.44) with an unknown amount of KOH. The solution is diluted to 1.00 L using deionized water. An aliquot of the solution is placed in a 1.00-cm cuvet. The absorbance of the solution at 285 nm is 0.7748. Using the measured absorbance value, calculate the concentrations of HA and A in the solution. Then calculate the pH of the solution. You may assume all activity coefficients are equal to unity. НА A- 2050 Molar absorptivity at 285 nm (M² cm) 456

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter14: Applications Of Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 14.6QAP: The accompanying data (1.00-cm cells) were obtained for the spectrophotometric titration 10.00 mL of...

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