Electrochemical cell

If transfer of electrons is involved in a chemical reaction, we call it as oxidation and redox reactions. Two electrodes are used in an electrochemical cell. These electrodes are kept in a solution of its own ions. Potential difference is developed in a system when charges are moved. In an electrochemical cell, charged particles undergo motion when free energy is released in a redox reaction. Electromotive force is the maximum potential difference between the two electrodes. In an electrochemical cell, the change of free energy of the redox reactions of the electrodes is transformed into electrical energy. There are mainly four types of electrochemical cells. They are Voltaic cell (Galvanic cell), Electrolytic cell, Concentration cell and Fuel cell. The common examples of galvanic cells are dry cells, lead storage battery, Ni-Cd battery etc.