5 ered out of question Cyclic voltammetry is a very powerful technique to obtain the information about kinetics, thermodynamics and mass transport for an electrode reaction. Diffusion coefficient is an important mass transport related parameter governing an electrode reaction. It may be determined using transient voltammetry. A species Red undergoes a reversible one-electron transfer reaction to form Ox, Red Ox+ e* An oxidation peak current of 2.08 x 105 A was obtained from a voltammetric experiment undertaken at 25 °C in an aqueous electrolyte medium containing 1.0 mM Red and 0.1 M KCI using a 3.0 mm diameter electrode at a scan rate of 100 mV s¹. Calculate the diffusion coefficient in the unit of cm² s¹ for Red using the Randles-Sevčik equation and choose the correct answer from the following list: Select one: O a. 1.2 x 10-6 O b. 2.4 x 106 O c. 2.4 x 10-5 O d. 1.2x 10-5 Your answer is incorrect. 4

5 ered out of question Cyclic voltammetry is a very powerful technique to obtain the information about kinetics, thermodynamics and mass transport for an electrode reaction. Diffusion coefficient is an important mass transport related parameter governing an electrode reaction. It may be determined using transient voltammetry. A species Red undergoes a reversible one-electron transfer reaction to form Ox, Red Ox+ e* An oxidation peak current of 2.08 x 105 A was obtained from a voltammetric experiment undertaken at 25 °C in an aqueous electrolyte medium containing 1.0 mM Red and 0.1 M KCI using a 3.0 mm diameter electrode at a scan rate of 100 mV s¹. Calculate the diffusion coefficient in the unit of cm² s¹ for Red using the Randles-Sevčik equation and choose the correct answer from the following list: Select one: O a. 1.2 x 10-6 O b. 2.4 x 106 O c. 2.4 x 10-5 O d. 1.2x 10-5 Your answer is incorrect. 4

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter23: Voltammetry

Section: Chapter Questions

Problem 23.1QAP

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