electrolysis: Electroplating

Electroplating

In electroplating, the plating metal is generally the anode, and the object to be plated is the cathode. A solution of a salt of the plating metal is the electrolyte. The plating metal is deposited on the cathode, and the anode replenishes the supply of positive ions, thus gradually being dissolved. Electrotype printing plates, silverware, and chrome automobile trim are plated by electrolysis.

The English scientist Michael Faraday discovered that the amount of a material deposited on an electrode is proportional to the amount of electricity used. The ratio of the amount of material deposited in grams to the amount of electricity used is the electrochemical equivalent of the material. Actual electric consumption may be as high as four times the theoretical consumption because of such factors as heat loss and undesirable side reactions.

Sections in this article:

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2024, Columbia University Press. All rights reserved.

See more Encyclopedia articles on: Chemistry: General