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Fundamentals Of Analytical Chemistry

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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A 0.1% Methylene blue solution is needed for the detection AFB (Acid
Fast Bacillus) in sputum smears.
To prepare this, 1±0.03 grams of methylene blue is dissolved in a
1000±0.36 mL water. Determine the relative uncertainty of the solution.
You will need to measure 30 mL of this solution using a pipette. You
only have a Class B 10-mL pipette (±0.04mL) and a Class A 5-
mL(±0.01mL) volumetric pipette. Is it more accurate to use the Class B
pipette three times or the Class A pipette six times?

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