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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A 25.0 mL aliquot was taken from a 500.0 mL sample of tonic water containing an unknown amount of quinine and diluted to a volume of 200 mL. At 347.5 nm, the fluorescence intensity of the diluted sample was measured 85.7 an arbitrary scale. Under similar conditions, a 27.5 ppm standard quinine solution had a fluorescence intensity of 185. Calculate the mass of quinine in the original tonic water sample in mg. Do not include units in your answer.
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