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

Appl Of Ms Excel In Analytical Chemistry

2nd Edition

ISBN:9781285686691

Author:Crouch

Publisher:Crouch

Chapter4: Least-squares And Calibration Methods

Section: Chapter Questions

Problem 9P

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PLEASE DO A B AND C THANK YOU SOOO MUCH!!!!!!!!