Explain electrolytic decomposition of water with the help of diagram.
During electrolysis of water, electricity is passed through water containing a few drops of sulphuric acid. Water breaks down to give its constituent elements as products i.e. hydrogen and oxygen. Following equation represents the electrolysis of water
The hydrogen gas is formed at the cathode while the oxygen gas is formed at the anode. Now we know that hydrogen gas is a combustible gas, while oxygen gas is a supporter of combustion. Also, hydrogen gas burns with a popping sound. Thus, when a burning match stick is brought close to the mouth of tube which contains the gas formed at cathode, then it will be observed that the gas burns with a popping sound. This confirms that hydrogen gas is formed at the cathode.
Similarly, when a glowing matchstick is brought close to the mouth of the tube containing gas formed at anode, it burns more brightly. This confirms oxygen is formed at anode.
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