When a solid changes into liquid, the entropy

Options

A. Becomes zero
B. Remains the same
C. Increases
D. Decreases

Answer

To determine how the entropy changes when a solid changes into a liquid, we can follow these steps:

### Step-by-Step Solution:

1. **Define Entropy**:
- Entropy is a measure of the disorder or randomness of the particles in a system. Higher entropy indicates greater disorder.

2. **Understand the States of Matter**:
- In the solid state, particles are closely packed and have limited movement, resulting in lower randomness and lower entropy.
- In the liquid state, particles are more loosely arranged and can move more freely, leading to higher randomness and higher entropy.

3. **Analyze the Phase Change**:
- When a solid transitions to a liquid (melting), the structure of the particles changes from a fixed arrangement to a more fluid and disordered state.

4. **Determine the Change in Entropy**:
- Since the transition from solid to liquid involves an increase in the freedom of movement of the particles and an increase in disorder, we conclude that the entropy of the system increases.

5. **Final Conclusion**:
- Therefore, when a solid changes into a liquid, the entropy of the system increases.

### Final Answer:
When a solid changes into a liquid, the entropy of the system increases.

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