Chemical Actions and Uses

The chemical effects produced when electric current passes through matter, especially electrolysis, and the practical uses of those effects.

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Electrolysis: A process in which electric current drives a nonspontaneous chemical reaction through an electrolyte. It is the main chemical action of current, decomposing or transforming substances.
Electroplating: The deposition of a metal coating on an object by electrolysis. It uses electrodeposition to improve appearance, corrosion resistance, or surface properties.
Electric current: The rate at which electric charge flows through a surface or circuit. The amount of charge delivered determines the extent of electrochemical change.
Electrolysis of water: The decomposition of water into hydrogen and oxygen using an electric current. It is a familiar example of current driving a chemical change that requires energy.
Electrolyte: A substance that conducts electricity through mobile ions when molten or dissolved in a solvent. Its mobile ions carry charge through the material being chemically changed.
Electrorefining: The purification of a metal by dissolving it at an anode and depositing it at a cathode. It uses controlled electrolysis to produce high-purity metals such as copper.
Ion: An atom or molecule with a net electric charge because it has lost or gained electrons. Ions transport charge through electrolytes and participate in electrode reactions.
Galvanic cell: An electrochemical cell that converts energy from a spontaneous redox reaction into electrical energy. It reverses electrolysis's energy direction: chemical change supplies rather than consumes current.
Electrode: An electrical conductor through which current enters or leaves an electrolyte or other medium. Chemical reactions occur at the electrode surfaces where current crosses into the electrolyte.
Hall–Héroult process: An industrial process that extracts aluminum by electrolyzing alumina dissolved in molten cryolite. It demonstrates how electrolysis enables large-scale production of reactive metals.