Here's why:
* Vapor Pressure: Every liquid has a tendency to evaporate, and its molecules escape into the gas phase. This escaping tendency creates a pressure called vapor pressure. The higher the temperature, the more molecules have enough energy to escape, and the higher the vapor pressure.
* External Pressure: This is the pressure exerted by the surrounding atmosphere on the liquid's surface.
* Boiling Point: When the vapor pressure of the liquid equals the external pressure, the liquid starts to boil. This is because the escaping molecules have enough energy to overcome the pressure pushing down on the liquid's surface.
Let me know if you'd like to know more about vapor pressure or boiling point!
