International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

What can be said about the energy of particles in a solid?

1. Energy is high, allowing fast movement

2. Energy is low, and they can move freely

3. Energy is moderate, leading to some movement

4. Energy is non-existent

The correct answer is: Energy is high, allowing fast movement

The energy of particles in a solid is characterized by being low compared to liquids and gases. In solids, particles are closely packed together in a fixed arrangement and do not have sufficient energy to move freely. Instead, they can only vibrate in place. This limited movement is a consequence of the strong intermolecular forces that hold the particles in their fixed positions, thus maintaining the solid's structure. The option suggesting that energy is high and allows for fast movement does not align with the behavior of particles in a solid. Solids are distinguished by their rigidity and defined shape, which are a result of their low kinetic energy, as the particles are not free to move about like they would in a liquid or gas. The correct answer would highlight the restricted movement and energy of solid particles as they vibrate rather than move freely or rapidly.