F.9. 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 6.76 mg/L DDT standard and 2.49 mg/L chloroform as the internalstandard, which produced peak areas of 4481 and 10923 for the DDT and chloroform, respectively.Determine the response factor (F).F =After establishing the response factor of the instrument, the researcher collected 7.65 g of spinach, homogenized the sample,and extracted the DDT using an established method, producing a 3.65 mL solution containing an unknown amount of extractedDDT. The researcher then prepared a sample for analysis that contained 0.500 mL of the unknown DDT solution and 2.00 mlof 10.56 mg/L chloroform, which was diluted to a final volume of 25.00 mL. The sample was analyzed using GCMS, producingpeak areas of 6725 and 13805 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

Answered: Image /qna-images/answer/4d0005e4-79d2-4cb9-abae-342a1ccc2fe5.jpg

Omatography mass spectrometry (GCMS). First attempts using external calibration proved difficult, as reproducibility and ernal standard agreement were poor. To overcome these problems, the researcher used the internal standard calibration hod with chloroform as the internal standard. begin, the researcher analyzed a sample containing 6.76 mg/L DDT standard and 2.49 mg/L. chloroform as the internal ndard, which produced peak areas of 4481 and 10923 for the DDT and chloroform, respectively. termine the response factor (F). fter establishing the response factor of the instrument, the researcher collected 7.65 g of spinach, homogenized the sample, nd extracted the DDT using an established method, producing a 3.65 mL solution containing an unknown amount of extracted ODT. The researcher then prepared a sample for analysis that contained 0.500 mL of the unknown DDT solution and 2.00 mL of 10.56 mg/L chloroform, which was diluted to a final volume of 25.00 mL.. The sample was analyzed using GCMS, producing meak areas of 6725 and 13805 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: me DDT /e spinach

Omatography mass spectrometry (GCMS). First attempts using external calibration proved difficult, as reproducibility and ernal standard agreement were poor. To overcome these problems, the researcher used the internal standard calibration hod with chloroform as the internal standard. begin, the researcher analyzed a sample containing 6.76 mg/L DDT standard and 2.49 mg/L. chloroform as the internal ndard, which produced peak areas of 4481 and 10923 for the DDT and chloroform, respectively. termine the response factor (F). fter establishing the response factor of the instrument, the researcher collected 7.65 g of spinach, homogenized the sample, nd extracted the DDT using an established method, producing a 3.65 mL solution containing an unknown amount of extracted ODT. The researcher then prepared a sample for analysis that contained 0.500 mL of the unknown DDT solution and 2.00 mL of 10.56 mg/L chloroform, which was diluted to a final volume of 25.00 mL.. The sample was analyzed using GCMS, producing meak areas of 6725 and 13805 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: me DDT /e spinach

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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A researcher was attempting to quantify the amount of dichlorodiphenyltrichloroethane (DDT) in spinach using gas chromatography mass spectrometry (GCMS). First attempts using external calibration proved difficult, as reproducibility and external standard agreement were poor. To overcome these problems, the researcher used the internal standard calibration method 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 internal standard, which produced peak areas of 4191 and 10585 for the DDT and chloroform, respectively. Determine the response factor (F). F =
A researcher was attempting to quantify the amount of dichlorodiphenyltrichloroethane (DDT) in spinach using gas chromatography mass spectrometry (GCMS). First attempts using external calibration proved difficult, as reproducibility and external standard agreement were poor. To overcome these problems, the researcher used the internal standard calibration method with chloroform as the internal standard. To begin, the researcher analyzed a sample containing 5.67 mg/L DDT standard and 1.84 mg/L chloroform as the internal standard, which produced peak areas of 4035 and 10177 for the DDT and chloroform, respectively. After establishing the response factor of the instrument, the researcher collected 11.53 g of spinach, homogenized the sample, and extracted the DDT using an established method, producing a 3.70 mL solution containing an unknown amount of extracted DDT. The researcher then prepared a sample for analysis that contained 1.00 mL of the unknown DDT solution and 2.00 mL of 10.25…
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