Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere. At sea level the boiling

point of water is 100 °C or 212 °F but at higher altitudes it drops to correspond with decreasing atmospheric pressures.

Boiling water is used as a method of making it potable by killing microbes and viruses that may be present. The sensitivity of different micro-organisms to heat varies. But if water is held at 100 °C (212 °F) for one minute, most micro-organisms and viruses are inactivated. Ten minutes at a temperature of 70 °C (158 °F) is also sufficient for most bacteria.

Boiling water is also used in several cooking methods including boiling, steaming and poaching.

 

Note:   The above text is excerpted from the Wikipedia article Boiling, which has been released under the GNU Free Documentation License.