What is the necessary condition for the existence of solids?

Options

A. Intermolecular forces should be weaker than thermal energy
B. Intermolecular forces should be stronger than thermal energy
C. Intermolecular forces should be equal to the thermal energy
D. No definite relationship between them

Answer

To determine the necessary condition for the existence of solids, we need to analyze the relationship between intermolecular forces and thermal energy.

### Step-by-Step Solution:

1. **Understanding Intermolecular Forces**:
- Intermolecular forces are the forces of attraction or repulsion between molecules. They play a crucial role in determining the physical state of a substance (solid, liquid, or gas).

2. **Understanding Thermal Energy**:
- Thermal energy is the energy that comes from the temperature of a substance. It is a measure of the kinetic energy of the particles in a substance. Higher thermal energy means that the particles move more vigorously.

3. **Condition for Solids**:
- For a substance to exist as a solid, the intermolecular forces must be strong enough to hold the particles closely together despite the thermal energy that tends to make them move apart.
- Therefore, the necessary condition for the existence of solids is that the **intermolecular forces must be stronger than the thermal energy** acting on the particles.

4. **Conclusion**:
- In summary, the necessary condition for the existence of solids is that the intermolecular forces must be greater than the thermal energy of the particles.

### Final Answer:
The necessary condition for the existence of solids is that the intermolecular forces must be stronger than the thermal energy.

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