CBSE Class 10 Answered

Dear Aksa, Hydrolysis means addition of water molecule. Hydrolysis is a reaction which usually means the cleavage of chemical bonds by the addition of water. Hydrolysis cleaves the non-water component in two parts. Electrolysis: It is the process of decomposition of a chemical compound in aqueous solutions or in a molten state, accompanied by a chemical change using direct current. For example: Manufacture of hydrogen – By the electrolysis of water Hydrogen is commercially obtained by the electrolysis of water. Water is a poor conductor of electricity. Thus, a less volatile acid such as sulphuric acid is added to the water to make it a good conductor of electricity. This is called acidulated water. On passing electric current through this acidulated water, water dissociates. H2O H+ + OH? H+, being positively charged, moves towards the cathode (negatively charged electrode). At cathode, H+ + e?? H H + H ? H2 Thus, the hydrogen gas is evolved at the cathode. OH?, being negatively charged, moves towards the anode (positively charged electrode). At anode, OH? ? e?? OH OH + OH ? H2O + O O + O ? O2 Oxygen is evolved at the anode. Hence, water dissociates to give hydrogen and oxygen by passing an electric current through acidulated water. 2 H2O ? 2 H2 + O2 (acidulated) (at cathode) (at anode) Electrolysis uses electrically charged probes called an anode and a cathode, submerged in salty water to split the hydrogen and oxygen atoms. These elements collect at either probe and are collected. Electrochemical cells uses the naturally occurring chemical reactions in specific elements such as zinc and carbon to produce a flow of electrons. By connecting the two terminals on these cells, the electrons can flow allowing the chemical reaction to take place.