The temperature at which a substance boils, or changes
from a liquid to a vapor or gas, through the formation
and rise to the surface of bubbles of vapor within
the liquid. In a stricter sense, the boiling point
of a liquid is the temperature at which its vapor
pressure is equal to the local atmospheric pressure.
Decreasing (or increasing) the pressure of the surrounding
gases thus lowers (or raises) the boiling point of
a liquid. The quantity of heat necessary to change
1 g of any substance from liquid to gas at its boiling
point is known as its latent heat of vaporization.