What is the term for the pressure exerted by the vapor of a liquid until equilibrium is reached?

The correct term for the pressure exerted by the vapor of a liquid until equilibrium is reached is vapor pressure. This concept is essential in understanding how liquids behave under various conditions, particularly when they are heated or contained in a closed environment. Vapor pressure is determined by the tendency of particles to escape from the liquid phase into the vapor phase; as more particles escape, the pressure of the vapor increases until it reaches equilibrium with the liquid. At this point, the rate of evaporation of the liquid equals the rate of condensation of the vapor, resulting in a stable pressure.

In contexts such as fire science, recognizing vapor pressure is crucial because it influences the behavior of flammable liquids and their potential to ignite when exposed to heat. Understanding how vapor pressure interacts with temperature and environmental conditions aids firefighters in assessing hazards and making informed decisions during operations.