Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
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Chapter 15, Problem 15.15QAP
The following lifetimes were measured for the chloride quenching of quinine sulfate given in Example 15-1.The fluorescence intensities are given in the example.
(a) Plot fluorescence intensity versus [Cl-].
(b) Plot the ratio of intensity to lifetime, F-
(c) Develop a normalization factor to correct the measured fluorescence intensity to that of the solution without quencher.
(d) Plot on the same graph Fversus [Cl-] and Fcorr versus (CI-].
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Quinine in a 1.553-g antimalarial tablet was dissolved in sufficient 0.10 M HCl to give 250 mL of solution.A 10.00-mL aliquot was then diluted to 50.00 mL with the acid. The fluorescence intensity for the dilutedsample at 347.5 nm provided a reading of 196 on an arbitrary scale. A standard 100-ppm quinine solutionregistered 125 when measured under conditions identical to those for the diluted sample. Calculate the massin milligrams of quinine in the tablet.
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Chapter 15 Solutions
Principles of Instrumental Analysis
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