JAMB - Chemistry (2017 - No. 34)
The reddish–brown rust on iron roofing sheets consists of
Fe3 + (H2O)6
FeO.H2O
Fe2O3.XH2O
Fe3O4.2H22O
توضیح
Iron [Fe] reacts with H2 in the presence of oxygen to form a rust.
4Fe + 3O2 → 2 Fe2O2
Fe2O3 + H2O → Fe2O3.H2O
4Fe + 3O2 → 2 Fe2O2
Fe2O3 + H2O → Fe2O3.H2O