Following are the two reasons beacuse of which Al is used for making utensils for cooking.
It does not undergo corrosion easily: Corrosion of aluminium occurs when the metal is exposed to oxygen, according to the following reaction:
4 Al(s) + 3 O 2 (g) → 2 Al 2 O 3 (s)
Thus a protective layer of aluminium oxide is formed on the surface of the metal, which renders the metal passive and prevents its further corrosion.