What do we call the process of changing from a liquid to a solid?

The process of changing from a liquid to a solid is known as freezing. During this phase transition, a substance loses energy as it cools, causing its particles to become more closely packed and organized, leading to the formation of a solid structure. For example, when water cools down to 0 degrees Celsius, it transforms into ice through freezing.

The other options represent different processes that are not related to the transition from liquid to solid. Melting refers to the transition from solid to liquid, while condensing involves the change from gas to liquid. Pumping does not pertain to a state change related to temperature and phase. Thus, freezing accurately describes the solidification of a liquid.