An unknown sample of Cu2+ gave an absorbance of 0.262 in an atomic absorption analysis. Then 1.00 mL of solution containing 100.0 ppm Cu2+ was mixed with 95.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask. The absorbance of the new solution was 0.500. a) Denoting the initial unknown concentration as [Cu2+]i, write an expression for the final concentration [Cu2+]f, after dilution. Units of concentration are ppm. b) In a similar manner, write the final concentration of added standard Cu2+ designated as [S]f. c.) Find the [Cu2+]I in the unknown

An unknown sample of Cu2+ gave an absorbance of 0.262 in an atomic absorption analysis. Then 1.00 mL of solution containing 100.0 ppm Cu2+ was mixed with 95.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask. The absorbance of the new solution was 0.500. a) Denoting the initial unknown concentration as [Cu2+]i, write an expression for the final concentration [Cu2+]f, after dilution. Units of concentration are ppm. b) In a similar manner, write the final concentration of added standard Cu2+ designated as [S]f. c.) Find the [Cu2+]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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