Which method does NOT prevent iron from rusting?
Answer and explanation
Correct answer: B. Keeping it in moist air
Rusting needs both water and oxygen, so moist air promotes it.
Answer: Keeping it in moist air.
Why not the others: Painting it: it keeps out water and oxygen. Galvanising it with zinc: zinc corrodes first. Attaching a magnesium block: magnesium is sacrificed instead.
Answer: Keeping it in moist air.
Why not the others: Painting it: it keeps out water and oxygen. Galvanising it with zinc: zinc corrodes first. Attaching a magnesium block: magnesium is sacrificed instead.
Practise more Metals and Corrosion.
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