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Manipal MET2019Chemistryd and f Block Elements

Pure conc. HNO ₃ make iron passive, as the surface is covered with protective layer of

Options

  1. AFe ₂ O ₃
  2. BFeO
  3. CFe ₃ O ₄
  4. DFe ( NO ₃ )₃

Correct answer

C. Fe ₃ O ₄

Step-by-step solution

HNO ₃ is a strong oxidising agent. So it oxidise iron and form a layer of Fe ₃ O ₄ that works as protective layer.

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