What phase change occurs when a gas turns into a liquid?

The phase change that occurs when a gas turns into a liquid is known as condensation. This process involves the cooling of gas particles, which decreases their energy, allowing them to come closer together and transition into the liquid state. A common example of this is when water vapor in the air cools and turns into liquid water, forming dew or fog.

In contrast, freezing refers to the transformation of a liquid into a solid, which is a different process. Evaporation is the phase change where a liquid becomes a gas, and melting describes the change from solid to liquid. Therefore, condensation is the term that accurately describes the transition from gas to liquid.