What is the boiling point?
What is the boiling point of water?
Generally speaking, the boiling point is 100 degrees Celsius or 212 degrees Fahrenheit.
Boiling point is the temperature at which the saturated vapor pressure of a liquid is equal to standard atmospheric pressure at sea level.
When liquid is heated to the boiling point, the liquid will evaporate into the air.
The boiling point of water depends on the atmospheric pressure, and atmospheric pressure changes with altitude.
The symbol for atmospheric pressure is mmHg, and the atmospheric pressure is 760 mmHg at sea level. A change of 27 mmHg in the atmospheric pressure
produces a change of 1 degree Celsius in the boiling point of water.
For every 1,000 feet you go above sea level, the atmospheric pressure decreases
by about 30 mmHg, which means that the boiling point temperature will also
decrease.
On high mountains, the atmospheric pressure is so low that the boiling point
of water is lowered several degrees. You might think that because you see water
boiling sooner, food will cook sooner, too. But cooking operations, like
cooking a hard-boiled egg, actually require longer than they do near sea
level. The water boils at a lower temperature, so the egg is cooking at a
lower temperature, so it will need to cook longer to become hard. The same
idea applies when cooking and baking other foods.
The efficiency of pressure cookers is due to the fact that the pressure
increases the boiling temperature several degrees above 100 degrees Celsius,
so food cooks faster.
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