Quinine in a 1.939-g tablet was to be analyzed by dissolving it with 0.10 M HCI to a final volume of exactly 500 mL. This solution was diluted by adding 50.00 mL to a 100.0 mL flask and diluting to the mark. Afterwards the fluorescence intensity was found to be 394 in arbitrary units. Under identical experimental conditions, a standard 150.0-ppm had an intensity of 184.Quinine in a 1.939-g tablet was to be analyzed by dissolving it with 0.10 M HCI to a final volume of exactly 500 mL. This solution was diluted by adding 50.00 mL to a 100.0 mL flask and diluting to the mark. Afterwards the fluorescence intensity was found to be 394 in arbitrary units. Under identical experimental conditions, a standard 150.0-ppm had an intensity of 184. Calculate the number of milligrams in the original sample.

Quinine in a 1.939-g tablet was to be analyzed by dissolving it with 0.10 M HCI to a final volume of exactly 500 mL. This solution was diluted by adding 50.00 mL to a 100.0 mL flask and diluting to the mark. Afterwards the fluorescence intensity was found to be 394 in arbitrary units. Under identical experimental conditions, a standard 150.0-ppm had an intensity of 184.Quinine in a 1.939-g tablet was to be analyzed by dissolving it with 0.10 M HCI to a final volume of exactly 500 mL. This solution was diluted by adding 50.00 mL to a 100.0 mL flask and diluting to the mark. Afterwards the fluorescence intensity was found to be 394 in arbitrary units. Under identical experimental conditions, a standard 150.0-ppm had an intensity of 184. Calculate the number of milligrams in the original sample.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 6P

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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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