MCQ
Iron becomes passive by ..................... due to formation of .....................
- Adil. $HCl, Fe_2O_3$
- ✓$80\%$ conc. $HNO_3, Fe_3O_4$
- Cconc. $H_2SO_4, Fe_3O_4$
- Dconc. $HCl, Fe_3O_4$
✓
Answer
Correct option: B.
$80\%$ conc. $HNO_3, Fe_3O_4$
b
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