Electrochemistry – Notes
Electrochemical and Galvanic Cells
Voltaic cells produce electrical energy, while electrolytic cells consume electrical energy.
Oxidation is a loss of electrons. Reduction is a gain of electrons. Oxidation and reduction occur together.
Standard electrode potentials are measured relative to the standard hydrogen electrode.
The half-reaction with the more positive electrode potential will undergo reduction. The half-reaction with the more negative electrode potential will undergo oxidation.
The potential difference between the two electrodes is called the cell potential, or the cell electromotive force, or emf for short.
Cell voltage is measured in volts.
Measurement of Electrode Potential
Arbitrarily, the standard hydrogen electrode is chosen as the standard reference electrode.
By convention, the potential of the standard hydrogen electrode is assumed as zero volts.
Standard electrode potentials are measured relative to the standard hydrogen electrode.
The emf of a cell is calculated as the difference of the two electrodes.
The standard oxidation potential is equal to minus standard reduction potential.




