Why does aluminum (Al) metal not undergo corrosion like iron does?A Al does not easily react with oxygen.B Fe gives cathodic protection to Al.C A protective layer of Al₂O₃ forms on the surface of Al.D Al is more difficult to oxidize than Fe.E An electrical circuit cannot be completed on a surface of Al.

The primary reason why aluminum does not corrode like iron is due to the formation of a protective layer of Al₂O₃ (aluminum oxide) on its surface. This layer prevents further oxidation of the aluminum underneath.

Here's a step-by-step explanation:

1. When aluminum is exposed to the atmosphere, it reacts with oxygen to form a thin layer of aluminum oxide (Al₂O₃). This is a process known as oxidation.

2. This aluminum oxide layer is extremely hard and resistant to further corrosion. It adheres strongly to the surface of the aluminum, protecting the metal underneath from further contact with the atmosphere.

3. Even if the aluminum surface is scratched and the metal is exposed, the aluminum will immediately react with the atmosphere to repair the aluminum oxide layer. This self-healing property is a key reason why aluminum is more resistant to corrosion than many other metals.

4. Iron, on the other hand, also forms an oxide (rust) when exposed to the atmosphere. However, this rust does not adhere well to the iron surface and flakes off, exposing more iron to the atmosphere and allowing the corrosion process to continue.

5. The other options mentioned (A, B, D, E) are not the primary reasons why aluminum does not corrode like iron. Aluminum does react with oxygen (though not as readily as some other metals), but the protective oxide layer prevents further reaction. Iron does not provide cathodic protection to aluminum. While aluminum is more difficult to oxidize than iron, this is not the primary reason for its resistance to corrosion. Finally, the completion of an electrical circuit on the surface of aluminum is not a factor in its corrosion resistance.