After establishing the response factor of the instrument, the researcher collected 14.58 g of spinach, homogenized the sample,and extracted the DDT using an established method, producing a 2.75 mL solution containing an unknown amount of extractedDDT. The researcher then prepared a sample for analysis that contained 0.750 mL of the unknown DDT solution and 1.25 mL of11.32 mg/L chloroform, which was diluted to a final volume of 25.00 mL. The sample was analyzed using GCMS, producingpeak areas of 8097 and 14601 for the DDT and chloroform, respectively.Calculate the amount of DDT in the spinach sample. Express the final answer as milligrams of DDT per gram of spinach.amount of DDT:mg DDT /g spinach A researcher was attempting to quantify the amount of dichlorodiphenyltrichloroethane (DDT) in spinach using gaschromatography mass spectrometry (GCMS). First attempts using external calibration proved difficult, as reproducibility andexternal standard agreement were poor. To overcome these problems, the researcher used the internal standard calibrationmethod with chloroform as the internal standard.To begin, the researcher analyzed a sample containing 7.13 mg/L DDT standard and 1.28 mg/L chloroform as the internalstandard, which produced peak areas of 4191 and 10585 for the DDT and chloroform, respectively.Determine the response factor (F).F =

Response factor (RF) = 0.0170 Concentration of chloroform calculation: Amount of chloroform taken…

After establishing the response factor of the instrument, the researcher collected 14.58 g of spinach, homogenized the sample, and extracted the DDT using an established method, producing a 2.75 mL solution containing an unknown amount of extracted DDT. The researcher then prepared a sample for analysis that contained 0.750 mL of the unknown DDT solution and 1.25 mL of 11.32 mg/L chloroform, which was diluted to a final volume of 25.00 mL. The sample was analyzed using GCMS, producing peak areas of 8097 and 14601 for the DDT and chloroform, respectively. Calculate the amount of DDT in the spinach sample. Express the final answer as milligrams of DDT per gram of spinach. amount of DDT: mg DDT /g spinach

After establishing the response factor of the instrument, the researcher collected 14.58 g of spinach, homogenized the sample, and extracted the DDT using an established method, producing a 2.75 mL solution containing an unknown amount of extracted DDT. The researcher then prepared a sample for analysis that contained 0.750 mL of the unknown DDT solution and 1.25 mL of 11.32 mg/L chloroform, which was diluted to a final volume of 25.00 mL. The sample was analyzed using GCMS, producing peak areas of 8097 and 14601 for the DDT and chloroform, respectively. Calculate the amount of DDT in the spinach sample. Express the final answer as milligrams of DDT per gram of spinach. amount of DDT: mg DDT /g spinach

EBK A SMALL SCALE APPROACH TO ORGANIC L

4th Edition

ISBN:9781305446021

Author:Lampman

Publisher:Lampman

Chapter88: Column Chromatography

Section: Chapter Questions

Problem 3P

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