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To protect steel and iron from rusting, a thin layer of which one of the following metals is applied?

Options

  1. AMagnesium
  2. BZinc
  3. CAluminium
  4. DLead

Correct answer

B. Zinc

Step-by-step solution

Zinc is used to protect the iron from corrosion because it is more electropositive than iron. Galvanising is a method of rust prevention. The iron or steel object is coated in a thin layer of zinc. This stops oxygen and water from reaching the metal underneath. Zinc is more electropositive than iron, hence it is more reactive than iron, so it oxidizes in preference to the iron object.

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