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1. An electrolytic cell is a device used to perform electrolysis (e.g., decomposition of water into hydrogen and oxygen gas, or bauxite into aluminum and other chemicals).

   In contrast, a galvanic cell, also known as a voltaic cell, converts chemical energy into electrical energy, by using spontaneous chemical reactions that take place at the electrodes. Each galvanic cell has its own characteristic voltage (defined as the energy release per electron transfer from one electrode to the other). A simple galvanic cell will consist only of an electrolyte and two different electrodes. (Galvanic cells can also be made by connecting two half-cells, each with its own electrode and electrolyte, by an ion-transporting “bridge”, usually a salt bridge; these cells are more complex.) The electrodes typically are two metals, which naturally have different reaction potentials relative to the electrolyte. This causes ions of one of the electrodes to preferentially enter the solution at one electrode, and another ion to leave the solution at the other electrode. This generates an electric current across the electrolyte, which will drive electric current through a wire that makes an exterior connection to each of the electrodes. A galvanic cell uses electrodes of different metals, whereas an electrolytic cell may use the same metal for cathode and anode.