Energy is needed when a solid at its melting point is converted into a liquid. Why ?

Explanation

To understand why energy is needed when a solid at its melting point is converted into a liquid, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding the Structure of Solids and Liquids**:
- In solids, particles are tightly packed together in a fixed arrangement. This close packing results in strong intermolecular forces of attraction between the particles.
- In liquids, particles are more loosely arranged compared to solids. They have more space between them, which leads to weaker intermolecular forces of attraction.

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