(b) Quinine in a 3.925-g antimalarial tablet was dissolved in sufficient 0.10 M HCI to give 1.000 L. Dilution of a 20.00 mL aliquot to 100.00 mL yielded a solution that gave a reading of 415 at 347.5 nm. A second 20.00 mL aliquot was mixed with 10.0 mL of 50-ppm quinine solution before dilution to 100 mL. The fluorescence intensity of this solution was 503. Calculate the percentage of quinine in the tablet.

(b) Quinine in a 3.925-g antimalarial tablet was dissolved in sufficient 0.10 M HCI to give 1.000 L. Dilution of a 20.00 mL aliquot to 100.00 mL yielded a solution that gave a reading of 415 at 347.5 nm. A second 20.00 mL aliquot was mixed with 10.0 mL of 50-ppm quinine solution before dilution to 100 mL. The fluorescence intensity of this solution was 503. Calculate the percentage of quinine in the tablet.

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 14.10QAP: The acid-base indicator HIn undergoes the following reaction in dilute aqueous solution:...

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