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Question
Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.
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Solution
Galvanisation involves coating iron objects with a layer of zinc to prevent oxygen and moisture from reaching the iron underneath. Because zinc is more reactive than iron, it loses electrons more easily. If the zinc layer is broken, a phenomenon called sacrificial protection occurs. The zinc preferentially undergoes oxidation (corrosion) before the iron, thereby protecting the underlying iron article from rusting.
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