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प्रश्न
Name a common metal which is highly resistant to corrosion.
उत्तर
Aluminium is a common metal that is highly resistant to corrosion because it is a highly reactive metal. It reacts easily with oxygen in air and forms a layer of aluminium oxide on its surface. This aluminium oxide layer is very tough and does not allow air to enter the metal for further reaction, thus preventing further corrosion of aluminium.
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संबंधित प्रश्न
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| A process of forming a thick oxide of aluminium when aluminium is exposed to air. This coat makes it resistant to corrosion. Resistance can be improved by making a layer of oxide thinker. In this technique, the aluminium article is the anode, and the electrolyte is sulphuric acid. The anode reaction results in the formation of a black-coloured film of aluminium oxide on the anode. By putting appropriate dyes in the electrolytic solution, both coloured surface with the decorative finish is achieved. Kitchen articles like anodised such as pressure cookers, pans and frames of sliding windows are applications of this technique. |
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