Download Equilibrium Electrochemistry •Chemical reactions in

Equilibrium Electrochemistry
•Chemical reactions in electrochemical cells
and Nernst Equation
•Combining standard Electrode Potentials to
determine the cell potential
•Obtaining reaction Gibbs Energies and
Reaction Entropies from cell potentials
•Relationship between the cell EMF and the
equilibrium constant.
Chemical reactions in
electrochemical cells and
Nernst Equation
Electrochemical Cell
ZnSO4
solution
CuSO4
solution
+
Potentiometer
with sliding
contact
The direction of spontaneous change in the cell can
be reversed by changing the electrochemical
potential of the electrons in one of the electrodes
relative to that in other electrode using an external
voltage source.
If this reaction is carried out reversibly,
Nernst Equation at 298.15 K,
The Nernst equation allows the emf
for an electrochemical cell to be
calculated if the activity is known for
each species and E0 is known.
Combining standard Electrode Potentials to
determine the cell potential
Example
Obtaining reaction Gibbs Energies and
Reaction Entropies from cell potentials
Relationship between the cell EMF and the equilibrium constant.
Example