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When electric current is passed through certain liquids or solutions that conduct electricity, chemical changes occur. This is called the chemical effect of electric current.

      

Fill three fourth of two beakers with dilute copper sulphate solution. Keep one solution for a comparative study. Dip two carbon electrodes in the other. Connect the two electrodes to the terminals of a battery.

By the passage of electricity, copper sulphate solution decomposes into sulphate ions

and copper ions .Among these copper ions are positive and sulphate ions are

negative. Copper ions reach the negative electrode receive two electrons and deposited as copper atoms on the negative electrode. So we can notice a fresh,shiny,reddish deposits on the negative electrode.The  copper ions in copper sulphate solution reached negative electrode and accept two electrons and deposited as copper atoms. So the blue colour of copper sulphate solution decreases. Due to the decrease in number of copper ions in the solution, the concentration of the solution decreases. Here electrical energy is used for the decomposition of the electrolyte.

When electric current passes through certain liquids or solutions that conduct electricity, chemical changes occur. Hydrogen and metals are collected on the cathode and nonmetals on the anode. This shows the chemical effect of electric current.