Chapter 2 Key Terms Flashcards
Anode
The electrode of an electrochemical cell at which oxidation occurs. Electrons flow away from the anode in the external circuit. Corrosion usually occurs and metal ions enter the solution at the anode
Cathode
The electrode of an electrochemical cell at which reduction is the principal reaction. Electrons flow towards the cathode in the external circuit
Cathodic protection
A technique to reduce the corrosion of a metal surface by making that surface the cathode of an electrochemical cell
Corrosion
The deterioration of material, usually metal, that results from a reaction with its enviroment
Corrosion cell
In order for corrosion to occur, certain conditions and elements are essential. This is the combination of anode, cathode, return oath and electrolyte
Corrosion inhibitor
A chemical substance or combination of substances that, when present in the environment, prevents or reduces corrosion
Crevice corrosion
Localised corrosion of a metal surface at, or immediately adjacent to, an area that is shielded from full exposure to the enviroment because of close proximity of the metal to the surface of snother metal
Electrolyte
A chemical substance containing ions that migrate in an electric field
Galvanic series
A list of metals and alloys arranged according to their corrosion potentials in a given environment
Generalised corrosion
Corrosion that is distributed more or less uniformly over the surface of a material
Localised corrosion
This occurs at discrete sites on the metal surface
Mill scale
The oxide layer formed during hot fabrication or heat treatment of metals
Passivation
A reduction of the anodic reaction rate of an electrode involved in corrosion
Pitting corrosion
Localised corrosion of a metal surface that is confines to a small area and takes the form of cavities called pits
Return path (metallic pathway)
This connects the anode and cathode, allowing passage of electrons, generated at the anode, to the cathode
