Fe+ ? --> Fe2O3Fe(OH)3 + ? --> Fe2O3

Question

Fe+ ? --> Fe2O3
Fe(OH)3 + ? --> Fe2O3

Answer 1

4Fe + 3O2 =2 Fe2O3
--------------------

Answer 2

Fe+O2=Fe2O3  
Fe(OH)3+CaO->Fe2O3+Ca(OH)2