ELECTROPLATING

"The process that produces a thin, metallic coating on the surface on another metal (or any other conductor, e.g., graphite). The metal substrate to be coated is made the cathode in an electrolytic cell where the cations of the electrolyte are the positive ions of the metal to be coated on the surface. When a current is applied, the electrode reaction occurring on the cathode is the reduction of the metal ions to metal. E.g., gold ions can be discharged form a gold solution to form a thin gold coating on a less expensive metal to produce ""custome"" jewelry. Similarly, chromium coating is often applied to steel surfaces to make them more ""rust resistant."" Electroplating is also used in the production of integrated circuits on computer chips and for other modern electronic instrumentation. The anode material can either be the metal to be deposited (in this case the electrode reaction is electrodissolution that continuously supplies the metal ions) or the anode can be of inert material and the anodic reaction is oxygen evolution (in this case the plating solution is eventually depleted of metal ions). Also called ""electrodeposition."" See also an Encyclopedia Article. "