A total of 5 mL of blood samples were treated with trichloroacetic acid to precipitate proteins. After centrifugation, the resulting solution is adjusted to pH 3 and extracted with 5 ml. of methyl isobutyl ketone containing the ammonium pyrolydine dithiocarbamate (APDC) complexing compound. The extract was then measured its absorbance using an atomic absorption spectrometer (AAS) at 7. 283.3 nm with an absorbance of 0.502. A total of 5 mL of standard Pb solution with concentrations of 0.4 and 0.6 ppm was also given the same treatment and resulted in absorbance of 0.396 and 0.599 ppm. Determine the pb concentration in the sample in ppm

A total of 5 mL of blood samples were treated with trichloroacetic acid to precipitate proteins. After centrifugation, the resulting solution is adjusted to pH 3 and extracted with 5 ml. of methyl isobutyl ketone containing the ammonium pyrolydine dithiocarbamate (APDC) complexing compound. The extract was then measured its absorbance using an atomic absorption spectrometer (AAS) at 7. 283.3 nm with an absorbance of 0.502. A total of 5 mL of standard Pb solution with concentrations of 0.4 and 0.6 ppm was also given the same treatment and resulted in absorbance of 0.396 and 0.599 ppm. Determine the pb concentration in the sample in ppm

Macroscale and Microscale Organic Experiments

7th Edition

ISBN:9781305577190

Author:Kenneth L. Williamson, Katherine M. Masters

Publisher:Kenneth L. Williamson, Katherine M. Masters

Chapter22: Oxidation: Cyclohexanol To Cyclohexanone; Cyclohexanone To Adipic Acid

Section: Chapter Questions

Problem 2Q

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A 50.0 mL juice extract is colorimetrically assayed using Nelson’s test. One milliliter (1.00 mL) of the solution and the standard glucose solution (concentration: 1mg/mL) were treated with freshly prepared Nelson’s reagent and arsenomolybdate reagent and then diluted to 10.0 mL separately in properly labeled test tubes. Absorbance at 480 nm for the standard is 1.702 and for the sample, 0.926. A. What is the principle behind the assay? B. Calculate the concentration of the reducing sugar in the 50.0 mL sample in mg/mL. Apply Beer-Lambert’s law: A=bc
A 50.0 mL juice extract is colorimetrically assayed using Nelson’s test. One milliliter (1.00 mL) of the solution and the standard glucose solution (concentration: 1mg/mL) were treated with freshly prepared Nelson’s reagent and arsenomolybdate reagent and then diluted to 10.0 mL separately in properly labeled test tubes. Absorbance at 480 nm for the standard is 1.702 and for the sample, 0.926. A. What is the principle behind the assay?
A 5.00-mL sample of blood was treated with trichloroacetic acid to precipitate proteins. After centrifugation, the resulting solution was brought to pH 3 and extracted with two 5-mL portions of methyl isobutyl ketone containing the lead-complexing agent APCD. The extract was aspirated directly into an air/acetylene flame and yielded an absorbance of 0.569 at 283.3 nm. Five-milliliter aliquots of standard solutions containing 0.400 and 0.600 ppm of lead were treated in the same way and yielded absorbances of 0.396 and 0.599. Please calculate the concentration of lead in the sample in ppm.
A 50.0 mL juice extract is colorimetrically assayed using Nelson’s test. One milliliter (1.00 mL) of the solution and the standard glucose solution (concentration: 1mg/mL) were treated with freshly prepared Nelson’s reagent and arsenomolybdate reagent and then diluted to 10.0 mL separately in properly labeled test tubes. Absorbance at 480 nm for the standard is 1.702 and for the sample, 0.926. Calculate the concentration of the reducing sugar in the 50.0 mL sample in mg/mL. Apply Beer-Lambert’s law: A=bc.
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A 5.00-mL sample of blood was treated with trichloroacetic acid to precipitate proteins. After centrifugation, the resulting solution was brought to pH 3 and extracted with two 5-mL portions of methyl isobutyl ketone containing the lead-complexing agent APCD. The extract was aspirated directly into an air/acetylene flame and yielded an absorbance of 0.527 at 283.3 nm. Five-milliliter aliquots of standard solutions containing 0.400 and 0.600 ppm of lead were treated in the same way and yielded absorbances of 0.396 and 0.599. Find the concentration of lead in the sample in ppm assuming that Beer’s law is followed.
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