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प्रश्न
Give a reason why rusting of iron is a chemical change but, the magnetization of iron is a physical change.
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उत्तर
Rusting of iron is a chemical change, as composition changes, the reddish-brown flaky powder is formed with new properties and is an irreversible, permanent change, but magnetization of iron is a temporary and reversible change with no change in composition and is a physical change.
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