A series of standards of a rhodamine derivative were measured with an excitation wavelength of 480 nm (2ex) and an emission wavelength of 620 nm (em). The following data was obtained: (i) (ii) (iii) Standard 1 2 3 4 5 Rhodamine Derivative Concentration (ppm) 1.9 4.0 5.8 8.2 10.0 Emission Intensity 1100 2150 3130 4350 5900 Explain the difference between the excitation wavelength and the emission wavelength. Using the data provided, determine the extinction coefficient in dm³.mg¹.cm¹ and the molar extinction coefficient in dm³.mole¹.cm¹. The rhodamine derivative has a molar mass of 480 g.mole-¹. If the unknown sample has a fluorescence emission intensity of 3899, calculate the concentration of the sample in parts per million (ppm) and moles dm-³ (molarity).

A series of standards of a rhodamine derivative were measured with an excitation wavelength of 480 nm (2ex) and an emission wavelength of 620 nm (em). The following data was obtained: (i) (ii) (iii) Standard 1 2 3 4 5 Rhodamine Derivative Concentration (ppm) 1.9 4.0 5.8 8.2 10.0 Emission Intensity 1100 2150 3130 4350 5900 Explain the difference between the excitation wavelength and the emission wavelength. Using the data provided, determine the extinction coefficient in dm³.mg¹.cm¹ and the molar extinction coefficient in dm³.mole¹.cm¹. The rhodamine derivative has a molar mass of 480 g.mole-¹. If the unknown sample has a fluorescence emission intensity of 3899, calculate the concentration of the sample in parts per million (ppm) and moles dm-³ (molarity).

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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