An unknown sample of Cu2+ gave an absorbance of 0.475 in an atomic absorption analysis. Then 5.00 mL of solution containing 75.0 ppm (= µg/mL) Cu2+ was mixed with 45.0 mL of unknown, and the mixture was diluted to 500.0 mL in a volumetric flask. a) Write an expression for the final concentration after dilution. b) Calculate the final concentration of the added standard. c) The absorbance of the new solution was 0.987. Find the initial concentration of Cu2+ in the unknown sample

An unknown sample of Cu2+ gave an absorbance of 0.475 in an atomic absorption analysis. Then 5.00 mL of solution containing 75.0 ppm (= µg/mL) Cu2+ was mixed with 45.0 mL of unknown, and the mixture was diluted to 500.0 mL in a volumetric flask. a) Write an expression for the final concentration after dilution. b) Calculate the final concentration of the added standard. c) The absorbance of the new solution was 0.987. Find the initial concentration of Cu2+ in the unknown sample

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter27: Molecular Fluorescence Spectroscopy

Section: Chapter Questions

Problem 27.9QAP

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