Electrolysis problems and uses

Electrolysis is widely used in industry. In copper refining an impure copper block is made the anode and pure copper the cathode; when current passes, the anode dissolves and pure copper collects on the cathode. Pure copper is important for wires because impurities raise the resistivity. In galvanostegy an object is made the cathode and coated with a thin layer of another metal (such as nickel, chromium or gold) — this protects from rust or decorates. In galvanoplasty a metal layer is deposited on a mould of an object to obtain an exact metal copy; the method was discovered in 1838 by the Russian scientist B. S. Jacobi. Aluminium is also obtained by electrolysis of a melt. Such work is done in factories by specialists, with poisonous solutions, wearing protective equipment.