2. What are the transmission and absorbance of a blank sample? From other substan 3. Using the data at right: CONCENTRATION PERCENT ABSORBANCE a. Calculate the absorbance of each sample. You will need to express the %T values as decimals before calculating the logarithms. (ppm) TRANSMISSION 0 100.0 100 74.1 (e.g., for T = 25%, A = -log 0.25 = 0.602) 200 54.9 C. b. Use the graph paper on the back of this page (or a spreadsheet) to plot absorbance vs. concentration. Make a proper graph, with labeled axes, uniform scales, etc. Use a ruler to draw the best-fit line. Use the graph to find the concentration of the un- known sample. (Draw dotted lines on the graph showing how you found your answer.) 300 40.7 400 30.1 500 22.3 unknown 60.3

2. What are the transmission and absorbance of a blank sample? From other substan 3. Using the data at right: CONCENTRATION PERCENT ABSORBANCE a. Calculate the absorbance of each sample. You will need to express the %T values as decimals before calculating the logarithms. (ppm) TRANSMISSION 0 100.0 100 74.1 (e.g., for T = 25%, A = -log 0.25 = 0.602) 200 54.9 C. b. Use the graph paper on the back of this page (or a spreadsheet) to plot absorbance vs. concentration. Make a proper graph, with labeled axes, uniform scales, etc. Use a ruler to draw the best-fit line. Use the graph to find the concentration of the un- known sample. (Draw dotted lines on the graph showing how you found your answer.) 300 40.7 400 30.1 500 22.3 unknown 60.3

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

Chapter20: Molecular Mass Spectrometry

Section: Chapter Questions

Problem 20.14QAP

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