Molecules in Solids

Options

A. are free to move about
B. cannot move
C. can slide over each other
D. tend to fly away

Explanation

**Step-by-Step Solution:**

1. **Understanding the Structure of Solids**:
- Solids are characterized by their molecules being tightly packed together. This close arrangement is due to strong intermolecular forces of attraction that hold the molecules in fixed positions.

2. **Properties of Molecules in Solids**:
- The tightly packed nature of molecules in solids results in a rigid structure. This rigidity means that the shape and volume of solids are definite and do not change easily.

3. **Movement of Molecules**:
- In solids, the molecules are not free to move around. They can only vibrate about their fixed positions due to the lack of space between them. This limited movement is a direct consequence of the strong intermolecular forces that keep the molecules in place.

4. **Conclusion**:
- Therefore, the properties of molecules in solids include being tightly packed, having strong intermolecular forces, forming a rigid structure, and being unable to move freely except for vibrations.