Page 14 - Pharmaceutical Analytical Chemistry II - Pharm D Clinical- 07-PA202

The measured E of this cell, Ecell = - 0.41 V ----- negative
This indicates that the cell in such schematic presentation works as
ELECTROLYTIC Cell

Applications to Standard Electrode
potential, E0

1. Calculation of Potentials of Electrodes at NON-Standard
Conditions

2. Calculation of Potentials of Electrochemical Cells,
• At Standard Conditions
• At Non-Standard Conditions

1-Calculation of Potentials of Electrodes at Non-Standard
Conditions

Nernst Equation: How does concentration affect

Electrode potential?

Consider the reversible half-reaction cC + dD + ......
aA + bB + …. + ne–

A,B,C,D: formulas for the participating species (atoms, molecules, or ions)
e– : represents electrons

a,b,c,d : number of moles of each species appearing in the half-reaction

E0 = Standard Electrode potential
R = gas constant, 8.3 J K–1 mol–1
T = temp, K
n = number of moles of electrons that appear in the half-reaction
F = Faraday constant = 96,485 Coulombs/mole

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