Give reasons for the following observation: The smell of hot sizzling food reaches you several metres away. But to get the smell from cold food you have to go close.

Explanation

**Step-by-Step Solution:**

1. **Understanding Diffusion:**
- Diffusion is the process by which molecules spread from an area of high concentration to an area of low concentration. The rate of diffusion depends on the kinetic energy of the molecules.

2. **Effect of Temperature on Molecules:**
- When food is heated, the temperature increases, which in turn increases the kinetic energy of the molecules in the food. This causes the molecules to move faster.

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