Both iron and aluminium combine slowly with oxygen at room temperature. Why is this reaction a problem for iron but not for aluminium?

Explanation

### Step-by-Step Solution

1. **Understanding the Reaction of Metals with Oxygen**:
- Both iron (Fe) and aluminum (Al) react with oxygen (O2) in the atmosphere at room temperature. This reaction leads to the formation of oxides.

2. **Formation of Aluminum Oxide**:
- When aluminum reacts with oxygen, it forms aluminum oxide (Al2O3). This oxide layer is hard and forms a protective barrier on the surface of the aluminum.

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