Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
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Question
Chapter 25, Problem 25.11QAP
Interpretation Introduction
Interpretation:
Scan rate at experiment 2 should be calculated.
Concept introduction:
The peak current can be represented as follows:
Here,
Ip = peak current
n = number of electrons transferred in the redox event
A = electrode surface area
C = concentration
D = diffusion coefficient
V = scan rate
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An analyst wants to find out the active surface of his electrode before conducting his analyzes. To do this, he carried out a series of measurements by cyclic voltammetry (CV) using a 1 mM solution of K4Fe(CN)6 dissolved in 0.1M NaCl. He recorded the anodic peak intensity (ip) corresponding to the oxidation of Fe(II) to Fe(III) as a function of the scanning speed (v) of the CV (see table). What is the active surface of the electrode?
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Chapter 25 Solutions
Principles of Instrumental Analysis
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