When we burn agarbatti in a room, its smell spreads in the entire room. Why?

Explanation

### Step-by-Step Solution:

1. **Understanding the Scenario**: When agarbatti (incense stick) is burned, it releases aromatic particles into the air.

2. **Defining Diffusion**: The spreading of the smell is primarily due to a process called diffusion. Diffusion is the movement of particles from an area of higher concentration to an area of lower concentration.

3. **Mechanism of Diffusion**: In the case of agarbatti, the aromatic particles are initially concentrated around the burning incense. As these particles move into the air, they spread out into areas where their concentration is lower.

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