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|electrolytic cell |
A device that contains two electrodes in contact with an electrolyte and that brings about a chemical reaction when connected to an outside source of electricity. The electrodes are made of metal or carbon, and when connected to direct current, one electrode becomes positively charged, and the other becomes negatively charged. This initiates the movement of ions in the electrolyte toward the electrodes: positive ions move toward the negative electrode and negative ions move toward the positive electrode. A chemical reaction then takes place at each electrode, with ions changing from positive to negative (or vice versa), or becoming neutralized. Electrolytic cells have many practical uses, including the recovery of pure metal from alloys, the plating of one metal with another, and the manufacture of chlorine and sodium hydroxide. Compare voltaic cell.