In each of the following question, a statement of Assertion (A) is given followed by a corresponding statement of Reason (R). Choose the correct answer as:
Assertion (A): HNO3 renders iron passive.
Reason (R): Iron reacts with HNO3 to form ferric nitrite.
Answer & explanation
Correct answer: option 3
Correct Reason: HNO3 reacts with Fe to form a thin impervious layer of ferrosoferric oxide (FeO.Fe2O3≡Fe3O4) on the surface of iron which protects it from further action.