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प्रश्न
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
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उत्तर
The galvanised iron-zinc oxide layer coating on iron objects prevents zinc and iron under it from corrosion. This happens because zinc is more reactive than iron. If the zinc layer is broken, zinc, being more reactive, gets oxidised before iron and prevents its corrosion.
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