What happens to molecular action when heat is removed from a substance?

When heat is removed from a substance, the molecular action decreases. This is because the energy associated with the motion of the molecules is reduced, causing them to vibrate less vigorously. As a result, the overall kinetic energy of the molecules diminishes. This phenomenon is particularly observable in processes such as cooling, where materials may undergo a transition from a gaseous to a liquid or a solid state—an example being water turning into ice. The molecules in a solid are much more closely packed and have limited movement compared to those in a gas, where they are more dispersed and energetic. Thus, it is clear that removing heat leads to a decrease in molecular activity.