Question

how corrosion of iron is different from corrosion of aluminium​

Answer 1

Answer:

iron is corroded when in comes in contact with air and moisture and develops rust.

Aluminium too reacts with the air to form aluminium oxide. Since it is a self protecting metal, this oxide layer prevents further oxidation.

Explanation:

Iron (Fe) combines with oxygen (O2) to form rust, or iron oxide (Fe2O3). The equation for this reaction is: 4Fe+ 3O2 → 2Fe2O.

Al+ O2 = Al2O3

Answer 2

Answer :

The corrosion of Iron has a very specific name in Chemistry, which is 'rusting'. The corrosion of no other metal is known as rusting. Furthermore, going into the chemical specifics of this reaction, the corrosion of Iron forms hydrated Ferric Oxide ( $Fe_{2} O_{3} . n H_{2} O$ ) where as Aluminium does not corrode when left in the open. For rusting to happen, Oxygen and water must be present in the immediate environment of Iron. The process rusting is usually hastened by the presence of salt.

Explanation :

There is no corrosion of Aluminium, as such, because upon introduction of Aluminium into the atmosphere it forms an outermost, impervious layer of Aluminium Oxide ( $Al_{2}O_{3}$ ) which prevents Oxygen or water from coming into contact with the raw layers of Aluminium below this outer covering.

Note that the formula for rust contains an 'n', which represents the variable number of moles of water of crystallisation that are integrated into the structure of hydrated Ferric Oxide.