An unknown sample of Mn2+ gave an absorbance of 0.392 in an atomic absorption analysis. Then 2.00 mL of solution containing 100.0 ppm of Mn2+ (=μg/mL) was mixed with 90.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask. The absorbance of the new solution was 0.600. The blank reading for this experiment is 0.010. Denoting the initial, unknown concentration as [Mn2+]i, write an expression for the final concentration, [Mn2+]f, after dilution. Units of the concentration are ppm. In a similar manner, write the final concentration of added standard Mn2+, designated as [S]f. Find [Mn2+]i in the unknown.

An unknown sample of Mn2+ gave an absorbance of 0.392 in an atomic absorption analysis. Then 2.00 mL of solution containing 100.0 ppm of Mn2+ (=μg/mL) was mixed with 90.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask. The absorbance of the new solution was 0.600. The blank reading for this experiment is 0.010. Denoting the initial, unknown concentration as [Mn2+]i, write an expression for the final concentration, [Mn2+]f, after dilution. Units of the concentration are ppm. In a similar manner, write the final concentration of added standard Mn2+, designated as [S]f. Find [Mn2+]i in the unknown.

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

Chapter10: Atomic Emission Spectrometry

Section: Chapter Questions

Problem 10.11QAP

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