Determining the absorbance of known concentrations for Solution A: What is the most sensitive wavelength for Solution A (meaning highest absorbance) Using this wavelength, we now place known concentrations of Sample A in the Spec 20 ma- chine and see the absorbances. Sample A concentrations 0.000Molar (distilled water) Absorbance using Spec 20 Instrument 0.000 0.020 Molar 0.050 Molar 0.100 Molar 0.150 0.382 0.550 0.150 Molar 0.950 0.200 Molar 1.230 What is the independent & dependent variables? What variables go on what axis? Graph the sample concentrations vs the absorbances on the graph paper be- Does this a direct or inverse relationship? low: Is this graph more linear or nonlinear? Determining the concentration of an unknown sample using the standard curve from above. Last initial Unknown Concentration from the graph Absorbance 563 799 199 A6 0.800 219 329 317 N2 0.720 491 968 791 LS 0.650 823 790 193 094 585 181 Y-4 1.150 T-8 0.850 373 556 036 M-12 0.960

Determining the absorbance of known concentrations for Solution A: What is the most sensitive wavelength for Solution A (meaning highest absorbance) Using this wavelength, we now place known concentrations of Sample A in the Spec 20 ma- chine and see the absorbances. Sample A concentrations 0.000Molar (distilled water) Absorbance using Spec 20 Instrument 0.000 0.020 Molar 0.050 Molar 0.100 Molar 0.150 0.382 0.550 0.150 Molar 0.950 0.200 Molar 1.230 What is the independent & dependent variables? What variables go on what axis? Graph the sample concentrations vs the absorbances on the graph paper be- Does this a direct or inverse relationship? low: Is this graph more linear or nonlinear? Determining the concentration of an unknown sample using the standard curve from above. Last initial Unknown Concentration from the graph Absorbance 563 799 199 A6 0.800 219 329 317 N2 0.720 491 968 791 LS 0.650 823 790 193 094 585 181 Y-4 1.150 T-8 0.850 373 556 036 M-12 0.960

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter26: Molecular Absorption Spectrometry

Section: Chapter Questions

Problem 26.10QAP

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