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Excel Worksheet #2: The Beer Lambert Law 2 NAME: Questions - This page must be printed, completed, and submitted electronically or as a paper copy to your TA IN ADDITION TO the Excel file saved previously. 1. Using one set of data from Table 1 above, calculate the molar absorptivity of the Cr³ solution using equation 1. Hint: rearrange the Beer-Lambert Law to solve for a. The pathlength is 1.0 cm and the units of molar absorptivity will be cm ¹M¹. 2. Using the molar absorptivity value calculated in question 1 above, determine the absorption of a solution with a concentration of Cr" of 0.0325 M. 3. Using the trendline from your plot, calculate the absorption of a solution with a concentration of Cr³ of 0.0325 M. Hint, check your Excel plot to see if concentration is the x or y axis. Substitute as appropriate into the equation of the trendline.
In this experiment, you will be given both absorbance (A) and concentration (C) data for a solution containing a chromium(III) ion, Cr³+. You will use Excel to generate an x-y plot of A versus C. You will use Excel to generate a trendline (line of best fit) for the data provided and will use that plot to answer a variety of questions. We will assume that the pathlength (b) stays the same throughout the experiment and is equal to 1 cm. Therefore, you will be able to calculate the molar absorptivity of the Cr³+, and the change of A is only caused by the change of the Cr³ concentration. Results The following data table gives concentration, C, and absorbance, A, data for a series of solutions that contain the chromium(III) cation. Table 1: Concentration and Absorbance Data for an Aqueous Solution Containing the Chromium(III) Cation.¹ Concentration of Cr³+ in solution (M) Absorbance 0.162 0.0100 0.326 0.0200 0.509 0.0300 0.678 0.0400 0.830 0.0500