What is the overall electrochemical reaction taking place in rusting

1.	What is the overall electrochemical reaction taking place in rusting
Answer» Rusting is a very complicated process which involves multiple steps. OVERALL it is 4Fe + 3O2 →2Fe2O3 But where is water? We all know that we NEED water for rusting! 2Fe + O2 + 2H2O → 2Fe(OH)2 4Fe(OH)2 + O2 + 2H2O→4Fe(OH)3 2Fe(OH)3 →Fe2O3 + 3H2O Overall: 4Fe + 2O2 + 4H2O → 4Fe(OH)2 4Fe(OH)2 + O2 + 2H2O→4Fe(OH)3 4Fe(OH)3 →2Fe2O3 + 6H2O And 4Fe + 3O2 → 2Fe2O3

Answer»

Rusting is a very complicated process which involves multiple steps. OVERALL it is

4Fe + 3O2 →2Fe2O3

But where is water? We all know that we NEED water for rusting!

2Fe + O2 + 2H2O → 2Fe(OH)2

4Fe(OH)2 + O2 + 2H2O→4Fe(OH)3

2Fe(OH)3 →Fe2O3 + 3H2O

Overall:

4Fe + 2O2 + 4H2O → 4Fe(OH)2

4Fe(OH)2 + O2 + 2H2O→4Fe(OH)3

4Fe(OH)3 →2Fe2O3 + 6H2O

And

4Fe + 3O2 → 2Fe2O3

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