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| Characteristics of Electrolysis |
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| Following are the characteristics of the electrolysis process: |
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| 1) Electrolytic reactions involve the gain of electrons at the cathode and loss of electrons at anode. |
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| 2) The cathode reaction is a reduction reaction as the cations accept electrons, while the anode reaction is an oxidation reaction as the anions give up or lose electrons. |
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| 3) Metals and hydrogen are set free at the cathode. Such elements are said to be electropositive. Non-metals are set free at the anode. Such elements are said to be electronegative. |
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| 4) The mass of a substance produced at the electrode is directly proportional to the quantity of electricity that passes through the electrolyte. |
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| 5) The electrolytic reaction occurs at the surface of the electrodes. The products, obtained directly at the electrode surface are called the primary products. If the primary products react further to form molecules or compounds, the products so obtained are called secondary products. |
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| In the electrolysis of aluminium oxide dissolved in cryolite, the primary product formed at the carbon anode is oxygen. This oxygen then combines with the carbon of the anode to form carbon dioxide, which is the secondary product. |
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