Problem of the Week 5: Due next Monday, Oct. 14th at the beginning of class. A 6.2179-g sample of sirloin steak was ashed to remove organic materials, and the residue dissolved in a small amount of HCI and diluted to volume in a 50- mL volumetric flask. Iron can be analyzed by atomic absorption at a wavelength of 248.3 nm. A 10.0 mL sample of the dissolved residue is mixed with 1.00 mL of water and the absorbance is measured to be 0.352> A second 10.0 mL sample of the digested steak is mixed with 900.0 μL of water and 100.0 μL of an iron standard containing 250.0 ug Fe/mL. The absorbance of this solution was determined to be 0.613. What is the concentration of iron in the steak in wt %? In ppm?

Problem of the Week 5: Due next Monday, Oct. 14th at the beginning of class. A 6.2179-g sample of sirloin steak was ashed to remove organic materials, and the residue dissolved in a small amount of HCI and diluted to volume in a 50- mL volumetric flask. Iron can be analyzed by atomic absorption at a wavelength of 248.3 nm. A 10.0 mL sample of the dissolved residue is mixed with 1.00 mL of water and the absorbance is measured to be 0.352> A second 10.0 mL sample of the digested steak is mixed with 900.0 μL of water and 100.0 μL of an iron standard containing 250.0 ug Fe/mL. The absorbance of this solution was determined to be 0.613. What is the concentration of iron in the steak in wt %? In ppm?

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter24: Introduction To Spectrochemical Methods

Section: Chapter Questions

Problem 24.16QAP

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