As hot gases cool, they change their state from gas to which of the following?

As hot gases cool, they undergo a process called condensation. In this process, the transition from the gaseous state to a liquid state occurs when the temperature decreases to a point where the gas molecules lose sufficient kinetic energy. This decrease in energy allows the gas to come together to form liquid droplets, which is commonly observed in the formation of clouds and dew. Thus, when asked what state hot gases change to as they cool down, the correct answer is liquid, since this is the direct transformation following cooling.

In contrast, the other options do not accurately represent the immediate state that gases transition to upon cooling. The term 'vapor' typically refers to the gaseous state of a substance that is normally a liquid or solid at room temperature, so it does not apply to the direct cooling of gases. A 'solid' state implies a different process involving further cooling and a change in molecular arrangement that occurs following the liquid state. Lastly, 'gas' would indicate no change in state, which is not correct when discussing the cooling of hot gases.