A liquid boils when its
A) vapor pressure is exactly 1 atmosphere.
B) vapor pressure is equal to, or greater than, the external pressure pushing on it.
C) temperature is equal to 273 K (standard temperature).
D) temperature is greater than room temperature.

Question

Quizplus · Accepted Answer

According to the boiling point theory, a liquid boils when its vapor pressure is equal to or greater than the external pressure pushing on it. This means that at the boiling point, the vapor pressure of the liquid is sufficient to overcome the external pressure applied to it, and the liquid starts to boil and evaporate into the atmosphere. The boiling point can vary depending on the external pressure, which is why water boils at a lower temperature in high-altitude areas where the atmospheric pressure is lower.

A Liquid Boils When Its