As part of an investigation on Pb in biological ecosystems, some grasses that grew along the road and were exposed to emissions from motor gasoline were collected. 6.2501 g of grass were calcined to destroy all organic matter, the inorganic residue was properly treated and finally made up to 100 mL. An aliquot of 50 mL of this solution was read in an atomic absorption spectrophotometer registering an absorbance of 0.1250; then 0.10 mL of a standard solution of 55 µg of Pb / mL were added to the other 50 mL, with this fortified sample, another absorbance measurement was made, which was 0.1798. Calculate the µg of Pb / g of grass

As part of an investigation on Pb in biological ecosystems, some grasses that grew along the road and were exposed to emissions from motor gasoline were collected. 6.2501 g of grass were calcined to destroy all organic matter, the inorganic residue was properly treated and finally made up to 100 mL. An aliquot of 50 mL of this solution was read in an atomic absorption spectrophotometer registering an absorbance of 0.1250; then 0.10 mL of a standard solution of 55 µg of Pb / mL were added to the other 50 mL, with this fortified sample, another absorbance measurement was made, which was 0.1798. Calculate the µg of Pb / g of grass

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter14: Applications Of Ultraviolet-visible Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 14.9QAP

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