Respuesta :

This is a redox reaction.
3Fe + 2O₂ → Fe₃O₄     (Fe⁺²O·Fe⁺³₂O₃)

Fe - 2e⁻ = Fe⁺²
Fe - 3e⁻ = Fe⁺³
O₂ + 4e⁻ = 2O⁻²

oxidation is the answer you are looking for

RELAXING NOICE
Relax