The New Student's Reference Work/Boiling-Point

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Boiling-Point, the temperature at which a liquid is transformed into vapor. The boiling-point varies with different liquids, while it changes with the amount of atmospheric pressure to which it may be exposed. When the boiling-point is normal at the sea-level, in high altitudes, where the air-pressure is light, liquids boil more slowly. So well-known is this that the heights of mountains are approximately measured by ascertaining the degree of temperature at which water boils. In highly elevated regions many substances cannot be cooked by boiling. A further fact is that when water contains foreign substances in solution the boiling-point is raised; in other words, the greater the amount of these substances a liquid contains, the higher within certain limits is the boiling-point of the liquid. Under normal atmospheric pressure, ether boils at 35° C., pure alcohol at 78°, while aniline boils at 183° C. Water boils at 100° Centigrade or 212° Fahrenheit.