Why does a substance’s vapor pressure increase when temperature rises?

A substance's vapor pressure increases with temperature because of the relationship between molecular kinetic energy and phase equilibrium.12

At any given temperature, a liquid or solid exists in equilibrium with its vapor, exerting a characteristic pressure known as vapor pressure. This pressure is a measure of the material's tendency to transition into the gaseous state. According to the kinetic theory of gases, the average energy of molecules depends on the temperature. As the temperature rises, a greater number of molecules possess sufficient kinetic energy to overcome the intermolecular forces holding them in the liquid or solid phase.1234

Consequently, more molecules escape into the vapor phase, which increases the pressure exerted by that vapor. This relationship is mathematically described by the Clausius-Clapeyron equation, which relates the change in vapor pressure to temperature and the latent heat of vaporization. When the vapor pressure eventually equals the surrounding atmospheric pressure, the substance reaches its boiling point.251