The liquid-vapor saturation temperature and the boiling point are related concepts but have slight differences:
Liquid-Vapor Saturation Temperature: The liquid-vapor saturation temperature, also known as the saturation temperature or the boiling temperature, refers to the temperature at which a substance exists in equilibrium between its liquid and vapor phases. At this temperature, the substance can undergo a phase change from liquid to vapor (boiling) or from vapor to liquid (condensation) at a given pressure. It represents the temperature at which the substance's vapor pressure equals the external pressure, resulting in a balanced coexistence of liquid and vapor.
Boiling Point: The boiling point of a substance is the specific temperature at which it changes from a liquid phase to a vapor phase, usually at a given pressure. It is the temperature at which the vapor pressure of the liquid equals or exceeds the atmospheric pressure (for example, at sea level, where the atmospheric pressure is approximately 1 atmosphere). When the substance reaches its boiling point, bubbles of vapor form within the liquid and rise to the surface, resulting in the release of vapor.
While the liquid-vapor saturation temperature represents the temperature at which a substance exists in equilibrium between its liquid and vapor phases, the boiling point refers specifically to the temperature at which boiling occurs, that is, the transition from liquid to vapor phase. The boiling point is dependent on both the substance itself and the surrounding pressure. As the pressure changes, the boiling point of a substance will also change.
In summary, the liquid-vapor saturation temperature is the temperature at which a substance exists in equilibrium between its liquid and vapor phases, whereas the boiling point is the specific temperature at which boiling, the transition from liquid to vapor phase, occurs at a given pressure.