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Question
Why do we apply paint on iron articles?
Solution 1
Iron articles are painted because it prevents them from rusting. When painted, the contact of iron articles with moisture and air is cut off. Hence, rusting is prevented.
Solution 2
Iron articles are painted to prevent them from rusting. When left unpainted, the metal surface comes into contact with atmospheric oxygen, and in the presence of moisture, it becomes iron (III) oxide. But if painted, the surface does not come into contact with moisture or air, thus preventing rust.
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