The copper concentration of an unknown water sample was analyzed by flame absorption spectroscopy using a standard addition approach. A series of standard solutions containing copper standard in increasing concentration were prepared and analyzed. A graph of absorbances versus copper standards (µg/mL) containing the constant amount of unknown water was plotted. All the standard solutions were then analyzed by atomic absorption using nitrous oxide/acetylene flame. (i) (ii) Determine the x-intercept value if the calibration curve obtained for the standard solution through the standard addition method is Y = 3.164X-3.246. Calculate the concentration (in µg/mL) of copper in the unknown water sample if the volume of the unknown water sample used in the preparation of each standard solution is 5 mL and the total volume for each standard is 7 mL.

The copper concentration of an unknown water sample was analyzed by flame absorption spectroscopy using a standard addition approach. A series of standard solutions containing copper standard in increasing concentration were prepared and analyzed. A graph of absorbances versus copper standards (µg/mL) containing the constant amount of unknown water was plotted. All the standard solutions were then analyzed by atomic absorption using nitrous oxide/acetylene flame. (i) (ii) Determine the x-intercept value if the calibration curve obtained for the standard solution through the standard addition method is Y = 3.164X-3.246. Calculate the concentration (in µg/mL) of copper in the unknown water sample if the volume of the unknown water sample used in the preparation of each standard solution is 5 mL and the total volume for each standard is 7 mL.

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter24: Introduction To Spectrochemical Methods

Section: Chapter Questions

Problem 24.28QAP

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