A student is analyzing a tap water sample for Mg by atomic absorption spectroscopy and has the following table of standards data: Conc. (ppm) 1.0 0.20 0.40 0.70 Absorbance 0.131 0.255 0.498 0.641 She prepared 3 dilutions of her tap water (see below). Which dilution is the best to use? Tap water dilution factor Absorbance 1:4 1:20 1:50 1.196 0.390 0.119 the 1:4 dilution is best the the 1:50 dilution is best any value could be used with equal precision the 1:20 dilution is best

A student is analyzing a tap water sample for Mg by atomic absorption spectroscopy and has the following table of standards data: Conc. (ppm) 1.0 0.20 0.40 0.70 Absorbance 0.131 0.255 0.498 0.641 She prepared 3 dilutions of her tap water (see below). Which dilution is the best to use? Tap water dilution factor Absorbance 1:4 1:20 1:50 1.196 0.390 0.119 the 1:4 dilution is best the the 1:50 dilution is best any value could be used with equal precision the 1:20 dilution is best

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

Chapter12: Atomic X-ray Spectrometry

Section: Chapter Questions

Problem 12.6QAP

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