Which concept explains the continual motion of particles in solids, liquids, and gases?

The kinetic theory provides a comprehensive framework for understanding the continual motion of particles in solids, liquids, and gases. According to this theory, the states of matter can be described by the behavior of their constituent particles, which are in constant motion.

In solids, though particles are closely packed and vibrate primarily in fixed positions, there is still motion present. In liquids, the particles have enough energy to move freely around one another, leading to a more dynamic and fluid state. Gases exhibit the highest level of particle motion, with particles moving rapidly and independently, occupying whatever volume is available to them.

This continual motion is essential for explaining various phenomena such as diffusion, pressure, and temperature variations within different states of matter. Therefore, the kinetic theory is fundamental for illustrating how particle motion differs across solids, liquids, and gases, making it the correct choice in this context.