After 10.0 mL of an aqueous solution containing 1.235 mg of a drug extracted with 5.0 mL of toluene the aqueous layer was found to contain 0.346 mg of the compound. (a) Calculate the distribution coefficient for the drug between the two solvents. (b) How many 10.0-mL extractions would be required to recover 99.0% of the drug from 20.0 mL of water? What volume of toluene would be used?

After 10.0 mL of an aqueous solution containing 1.235 mg of a drug extracted with 5.0 mL of toluene the aqueous layer was found to contain 0.346 mg of the compound. (a) Calculate the distribution coefficient for the drug between the two solvents. (b) How many 10.0-mL extractions would be required to recover 99.0% of the drug from 20.0 mL of water? What volume of toluene would be used?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter16: Applications Of Neutralization Titrations

Section: Chapter Questions

Problem 16.7QAP

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Exactly 5.00-mL aliquots of a methanol solution containing an unknown amount of methamphetamine were measured into 50.00-mL volumetric flasks. The following volumes of a standard methanol solution of methamphetamine containing 2.000 ug/mL of methamphetamine were then introduced into each flask and the mixture was diluted to volume with 0.000, 0.500, 1.00, 1.50 and 2.00 mL of methanol. 1 uL of these solutions was then injected into a gas chromatograph and the following respective peak areas were measured: 326, 480, 641, 802, and 956 (all peak areas were x 103). Plot the data Using the plot from (a), calculate the concentration of methamphetamine in the unknown. Derive a least squares equation from the data. Calculate the concentration of methamphetamine from the equation in (c).
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