boiling point

boiling point The temperature at which the saturation vapour pressure of a liquid becomes equal to the external atmospheric pressure. Bubbles (the gaseous phase) form in the liquid, and the addition of heat does not cause a rise in temperature. Because the boiling point is dependent on pressure, it is normally quoted for one standard atmospheric pressure (1013.25 hPa). For water it decreases by 3.3°C per 1000 m increase in altitude
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