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Electrochemistry is the study of production of electricity from energy released during spontaneous chemical reactions and the use of electrical energy to bring about non-spontaneous chemical transformations. The subject is important both for theoretical and practical considerations. A large number of metals, sodium hydroxide, chlorine, fluorine and many other chemicals are produced by electrochemical methods. Batteries and fuel cells convert chemical energy into electrical energy and are used on large scale in various instruments and devices. The reactions carried out electrochemically can be energy sufficient and less polluting. Thus study of electrochemistry is important for creating new technologies that are ecofriendly. The transformation of sensory signals through cells to brain and vice versa and communication between the cells are known to have electrochemical origin.