Why do we apply paint on iron articles?

Explanation

### Step-by-Step Solution:

1. **Understanding the Problem**: The question asks why we apply paint on iron articles. The focus is on the protection of iron from a specific issue.

2. **Identifying the Issue**: Iron is a metal that is prone to rusting when it comes into contact with moisture (water) and air (oxygen). Rusting is a chemical reaction that leads to the deterioration of iron.

3. **Explaining Rusting**: When iron is exposed to moisture and oxygen, it reacts to form iron oxide, commonly known as rust. This process can weaken the iron structure and lead to damage over time.

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