Concept explainers
(a)
Interpretation:
A spreadsheet should be created to calculate the standard electrode potential for the Ag-AgCl electrode.
Concept introduction:
Overall equation:
Activity coefficient of ions can be calculated by Debye-Huckel equation,
Zx − charge on the species X
Ionic strength is defined by the equation,
C1, C2, C3 − molar concentrations of various ions in the solution
Z1, Z2, Z3 − charges on the ions.
For the electrolyte AmBn, the mean activity coefficient is given by
(b)
Interpretation:
The values obtained in part (a) for the activity coefficients and standard potential should be compared with those of MacInnes and if there are any differences, a possible reason for the discrepancies should be suggested.
Concept introduction:
Overall equation:
(c)
Interpretation:
The mean, standard deviation, 95 % confidence interval, and other useful statistics for the standard potential of the Ag-AgCl electrode should be found by using descriptive statistics function of Excel.
Concept introduction:
Overall equation:
(d)
Interpretation:
The analysis results and the quality of the MacInne’s results should be compared and discussed.
Concept introduction:
Overall equation:
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Principles of Instrumental Analysis
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- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning