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How does condensation change a gas into a liquid?

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Diagram showing four physical states of matter: solid with tightly packed molecules, liquid with loosely packed molecules, gas with widely spaced molecules, and plasma with free electrons and nuclei, each labeled with descriptions and an arrow indicating increasing energy. — phase States of matter.

Condensation is the phase transition in which a substance changes from a gas into a liquid or solid. This process typically occurs when a gas comes into contact with a surface that is cooler than the gas itself, or when the vapor pressure of the substance exceeds the vapor pressure of the liquid phase at the current temperature.12

At the molecular level, gas particles move rapidly and are generally far enough apart to escape each other's influence. When a gas is cooled, these particles lose kinetic energy, causing them to move more slowly. As their speed decreases, the particles begin to linger in each other's vicinity, allowing intermolecular forces—such as dipole-dipole interactions—to overcome their reduced kinetic energy and pull them together into a liquid state.34

Condensation is an exothermic process, meaning it releases heat into the surroundings. The energy released during this transition is known as the latent heat of vaporization (or liquefaction).1235