WHY ALUMINIUM DID NOT CORRODE FASTER THAN IRON , ALTHOUGH IT IS MORE REACTIVE......??????

We know Aluminium is more reactive than Iron.



So it reacts faster with the oxygen in the air forming Aluminium oxide,



Aluminium oxide is very unreactive , because once the oxide layer forms on the aluminium surface , it binds very tightly to the surface of the Aluminium , so no cracks can form that cause further corrosion.




This idea is used to prevent the Iron from corrosion by covering it with a thin layer of less reactive metal.




This process of covering of metal is known as Galvanizing.

;)