4 FeS2 + 15 O2 + 8 H2O → 2 Fe2O3 + 16 H+ + 8 (SO4)2-
This is an oxidation-reduction (redox) reaction:
8 S-I - 56 e- → 8 SVI (oxidation)
4 FeII - 4 e- → 4 FeIII (oxidation)
30 O0 + 60 e- → 30 O-II (reduction)
FeS2 is a reducing agent, FeS2 is a reducing agent, O2 is an oxidizing agent.
Reactants:
Products:
- Fe2O3 – Iron(III) oxide
- Other names: Ferric oxide , Hematite , Ferric iron
- Appearance: Red-brown solid ; Reddish brown-to-black crystals or powder ; Reddish-brown solid. [Note: Exposure to fume may occur during the arc-welding of iron.] ; A fine, red powder of ferric oxide. [Note: Usually used in cake form or impregnated in paper or cloth.]
- H+
- SO42- – Sulfate