Chloroform is used as an internal standard in the determination of the pesticide deltamethrin. To calibrate the method a mixture of 0.500 mM of chloroform and 0.800 mM of deltamethrin which produced signals of 15.3 (w.a.) and 10.1 (w.a.) for chloroform and deltamethrin, respectively. To prepare the sample, 10.00 mL of a sample of unknown concentration of deltamethrin and 10.10 μL of pure chloroform (FW = 119.39 g/mol, ρcloroformo = 1.484 g/L) is homogenized and diluted with water to the 100.00 mL mark in a volumetric flask. After preparing the sample, the observed signals of 30.0 (a.u.) and 20.7 (a.u.) for chloroform and deltamethrin, respectively, are observed. 1. Determine the response factor (K) for the method. 2.Determine the millimolar (mM) concentration of chloroform added to the sample. Remember that the final volume of the solution is 100.00 mL. 3.Determine the millimolar (mM) concentration of deltamethrin in the sample. 4.If the concentration of deltamethrin should not exceed 20.00 mM in drinking water Determine whether or not the water sample tested is considered potable water. Briefly explain your answer.

Chloroform is used as an internal standard in the determination of the pesticide deltamethrin. To calibrate the method a mixture of 0.500 mM of chloroform and 0.800 mM of deltamethrin which produced signals of 15.3 (w.a.) and 10.1 (w.a.) for chloroform and deltamethrin, respectively. To prepare the sample, 10.00 mL of a sample of unknown concentration of deltamethrin and 10.10 μL of pure chloroform (FW = 119.39 g/mol, ρcloroformo = 1.484 g/L) is homogenized and diluted with water to the 100.00 mL mark in a volumetric flask. After preparing the sample, the observed signals of 30.0 (a.u.) and 20.7 (a.u.) for chloroform and deltamethrin, respectively, are observed. 1. Determine the response factor (K) for the method. 2.Determine the millimolar (mM) concentration of chloroform added to the sample. Remember that the final volume of the solution is 100.00 mL. 3.Determine the millimolar (mM) concentration of deltamethrin in the sample. 4.If the concentration of deltamethrin should not exceed 20.00 mM in drinking water Determine whether or not the water sample tested is considered potable water. Briefly explain your answer.

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter14: Chromatography

Section: Chapter Questions

Problem 9P

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