Which of the following is the magnetic oxide of iron?
Answer & explanation
Correct answer: option 2
Hematite (Fe2O3) is an anti-ferromagnetic material below the Morin transition at 250 K, and a canted anti-ferromagnet or weakly ferromagnetic above the Morin transition.
Magnetite (Fe3O4) is a ferrimagnetic material, which is also easily available and possesses considerable magnetic properties
Rest are non-magnetic at all temperatures.