In 1800, a British chemist, William Nicholson showed that when electrodes were immersed in water and current was passed through water; bubbles of oxygen and hydrogen were produced. Oxygen bubbles were formed at the electrode connected to the positive terminal. Hydrogen bubbles were formed at the electrode connected to the negative terminal.
When electric current is passed through a conducing solution, some chemical reaction takes place in the solution. This is called chemical effect of electric current. Some of the chemical effects of electric current are as follows: