A) Phenol Red is a weakly acidic dye which is yellow in the HA form and red in the A form. What concentration of Phenol Red is required to obtain an absorbance of 0.50 at 550 nm at pH 7.8? Note: ε550 of A = 2.5 x 104 M-1 cm-1; ε550 of HA = 0; pKa = 7.8. B) What would the absorbance of the solution in part (a) be if the pH was 8.8?

A) Phenol Red is a weakly acidic dye which is yellow in the HA form and red in the A form. What concentration of Phenol Red is required to obtain an absorbance of 0.50 at 550 nm at pH 7.8? Note: ε550 of A = 2.5 x 104 M-1 cm-1; ε550 of HA = 0; pKa = 7.8. B) What would the absorbance of the solution in part (a) be if the pH was 8.8?

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter23: Amines

Section: Chapter Questions

Problem 23.32P: Suppose you have a mixture of these three compounds. Devise a chemical procedure based on their...

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