POTENTIAL-PH DIAGRAM

"A diagram often used in the field of corrosion to indicate the corrosion tendency and stability of a metal in aqueous solutions. The equilibrium potential of the metal is plotted against the pH of the solution, usually for a series of concentrations of the metal ion. The curves demarcate potential-pH domains where a species of the metal is predominant in equilibrium, this can be the metal, its ion, oxide, or hydroxide. In simplified version, the diagram can indicate the potential-pH domains where the metal is immune to corrosion, corrodes, or passivates. The diagrams must be used with some caution because they represent equilibrium conditions and the corrosion tendency is also influenced by kinetic effects. Also called ""Pourbaix diagram."" See also an Encyclopedia Article. "