The absorbance of a cationic iron(II) sample solution was measured in a spectrophotometer, but the instrument returned an error because the absorbance was too high. The sample was then diluted by using a pipette to take 100.0 μLμL of the sample and injecting it into a cuvette already containing 2.00 mLmL of water (total volume is 2.00 mLmL + 100.0 μLμL). The absorbance value of the diluted solution corresponded to a concentration of 7.71×10−6 M M . What was the concentration of the original solution? Express the concentration to three significant figures with the appropriate units.

The absorbance of a cationic iron(II) sample solution was measured in a spectrophotometer, but the instrument returned an error because the absorbance was too high. The sample was then diluted by using a pipette to take 100.0 μLμL of the sample and injecting it into a cuvette already containing 2.00 mLmL of water (total volume is 2.00 mLmL + 100.0 μLμL). The absorbance value of the diluted solution corresponded to a concentration of 7.71×10−6 M M . What was the concentration of the original solution? Express the concentration to three significant figures with the appropriate units.

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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