4. To analyze the Cu(NO3)2 unknown solution in Part 3, your group constructed a plot of absorbance vs. concentration, commonly called a calibration curve or standard curve. The absorbance at the top of the peak (i.e., at the wavelength of maximum absorbance) was chosen for these measurements. What is the potential advantage of using the wavelength of maximum absorbance, rather than some other wavelength? Can you think of a situation in which you might want to choose a different wavelength? (Hint: Scientists often do not have the luxurý of analyzing pure substances dissolved in distilled water!)

4. To analyze the Cu(NO3)2 unknown solution in Part 3, your group constructed a plot of absorbance vs. concentration, commonly called a calibration curve or standard curve. The absorbance at the top of the peak (i.e., at the wavelength of maximum absorbance) was chosen for these measurements. What is the potential advantage of using the wavelength of maximum absorbance, rather than some other wavelength? Can you think of a situation in which you might want to choose a different wavelength? (Hint: Scientists often do not have the luxurý of analyzing pure substances dissolved in distilled water!)

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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3. Using the graph provided, find the concentration of a solution that had an absorption of 0.269 when measured at 460 nm in a 1.0 cm cuvette. Absorbance vs. Concentration 0.45 0.4- y = 4.07x - 0.0046 R = 0.99353 0.35- %3D 0.3- 0.25 0.2- 0.15 - 0.1- 0.05 0.000 0.020 0.040 0.060 0.080 0.100 0.120 Concentration (mM) Absorbance at 460 nm
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