Final answer:
The kinetic-molecular theory describes the behavior of solids, liquids, and gases, based on the motion of particles. It is most precisely aligned with the properties of gases through the concept of an ideal gas, though it also applies to solids and liquids with different particle arrangements and movements.
Step-by-step explanation:
The kinetic-molecular theory explains the behavior of solids, liquids, and gases. It is based on the idea that matter is composed of small particles in constant motion. While it is most often associated with gases, as they follow the theory's assumptions most closely, it is also applicable to solids and liquids. For gases, an ideal gas is a hypothetical gas that perfectly fits all the assumptions of the kinetic-molecular theory. Although no real gases are truly ideal, they often behave very similarly to an ideal gas under typical conditions. In solids, particles vibrate in fixed positions but do not move around. Liquids have particles that move past each other yet remain in contact. Gases have particles that move independently, except when colliding with one another or the walls of their container.