1, name: fe2o3 is Fe2O3, fe3o4 is Fe3O4.
2. Color: fe2o3 is reddish brown and fe3o4 is black.
3. Features: fe2o3 has magnetic attraction, while fe3o4 has no magnetic attraction.
4. Valence: The valence of fe2o3 is +3, while fe3o4 has no valence.