EXPERIMENT 13: DETERMINATION OF DYE CONCENTRATION BY SPECTROPHOTOMETRY 1. You have been assigned solution number 3 to prepare. Calculate the concentration of Allura Red in this solution. 2. A student has found the following absorbance vs. concentration data. Concentration, M 9.80 x 10-6 6.35 x 10-6 4.12 x 10-6 1.43 x 10-6 Absorbance, A 0.810 0.522 0.333 0.101 Plot the absorbance (y-axis) versus concentration (x-axis) on graph paper. Draw the best straight line through the plotted points using a straight edge. Alternatively, plot the absorbance vs. concentration using a program such as Excel and do a least-squares fit to determine the best-fit line. Attach your graph to this pre-lab. 3. What is the slope of the best-fit line if taken from Excel? If done by hand, show your work. Remember to put the proper units on the slope.

EXPERIMENT 13: DETERMINATION OF DYE CONCENTRATION BY SPECTROPHOTOMETRY 1. You have been assigned solution number 3 to prepare. Calculate the concentration of Allura Red in this solution. 2. A student has found the following absorbance vs. concentration data. Concentration, M 9.80 x 10-6 6.35 x 10-6 4.12 x 10-6 1.43 x 10-6 Absorbance, A 0.810 0.522 0.333 0.101 Plot the absorbance (y-axis) versus concentration (x-axis) on graph paper. Draw the best straight line through the plotted points using a straight edge. Alternatively, plot the absorbance vs. concentration using a program such as Excel and do a least-squares fit to determine the best-fit line. Attach your graph to this pre-lab. 3. What is the slope of the best-fit line if taken from Excel? If done by hand, show your work. Remember to put the proper units on the slope.

Chemistry & Chemical Reactivity

10th Edition

ISBN:9781337399074

Author:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Publisher:John C. Kotz, Paul M. Treichel, John Townsend, David Treichel

Chapter4: Stoichiometry: Quantitative Information About Chemical Reactions

Section: Chapter Questions

Problem 77PS

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