What is the process by which gas changes into a liquid due to cooling?

The process by which gas changes into a liquid due to cooling is known as condensation. During condensation, the molecules in the gas lose energy as the temperature decreases, resulting in the molecules coming closer together and forming liquid droplets. This process is commonly observed when water vapor in the air cools down on a cold surface, such as a glass of ice water, creating moisture on the outside of the glass.

In contrast, evaporation refers to the process of liquid turning into gas, usually due to heating. Fusion involves the transition from solid to liquid, often referred to as melting, and solidification is the process of a liquid turning into a solid. Therefore, condensation is specifically the term used to describe the transition from gas to liquid due to cooling.