Extension Questions 1. A sample with an unknown concentration of Cr(NO3)3 has an absorbance of 0.68 at A of 426 nm. A calibration curve was produced for Cr(NO3)s and is shown below in Figure 1. Absorbance 0.5 4.63E-03*x + 4.4E-03 0.4 0.3 0.2 0.1 0 25 50 75 100 Concentration (mM) Figure 1. Calibration curve for Cr(NO) collected at 426 nm a. Determine the molar absorptivity (E) ifa 1.5 cm path length cuvette was used to collect data. Utilize the slope of the calibration curve above to determine the molar absorptivity value. b. Determine the concentration (mM) of Cr(NO3) in the unknown solution. n 9 c. A different lab group used a 1.0 cm path length cuvette in the preparation of a calibration curve using the same concentrations of Cr(NO3)3 space below, quantitatively draw out what the new calibration curve would look like. as in Figure 1. In the Include the axes labels and numerical values. Absorbance

Extension Questions 1. A sample with an unknown concentration of Cr(NO3)3 has an absorbance of 0.68 at A of 426 nm. A calibration curve was produced for Cr(NO3)s and is shown below in Figure 1. Absorbance 0.5 4.63E-03*x + 4.4E-03 0.4 0.3 0.2 0.1 0 25 50 75 100 Concentration (mM) Figure 1. Calibration curve for Cr(NO) collected at 426 nm a. Determine the molar absorptivity (E) ifa 1.5 cm path length cuvette was used to collect data. Utilize the slope of the calibration curve above to determine the molar absorptivity value. b. Determine the concentration (mM) of Cr(NO3) in the unknown solution. n 9 c. A different lab group used a 1.0 cm path length cuvette in the preparation of a calibration curve using the same concentrations of Cr(NO3)3 space below, quantitatively draw out what the new calibration curve would look like. as in Figure 1. In the Include the axes labels and numerical values. Absorbance

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 11P

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