carbonic acid
 碳酸
 carbonic acid 名詞
 碳酸,二氧化碳
 Me·phit·ic Me·phit·ic·al a.
 1. Tending to destroy life; poisonous; noxious; as, mephitic exhalations; mephitic regions.
 2. Offensive to the smell; as, mephitic odors.
 Mephitic air Chem., carbon dioxide; -- so called because of its deadly suffocating power. See Carbonic acid, under Carbonic.
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 Car·bon·ic a.  Chem. Of, pertaining to, or obtained from, carbon; as, carbonic oxide.
 Carbonic acid Chem., an acid HO.CO.OH, not existing separately, which, combined with positive or basic atoms or radicals, forms carbonates. In common language the term is very generally applied to a compound of carbon and oxygen, CO2, more correctly called carbon dioxide. It is a colorless, heavy, irrespirable gas, extinguishing flame, and when breathed destroys life. It can be reduced to a liquid and solid form by intense pressure. It is produced in the fermentation of liquors, and by the combustion and decomposition of organic substances, or other substances containing carbon. It is formed in the explosion of fire damp in mines, and is hence called after damp; it is also know as choke damp, and mephitic air. Water will absorb its own volume of it, and more than this under pressure, and in this state becomes the common soda water of the shops, and the carbonated water of natural springs. Combined with lime it constitutes limestone, or common marble and chalk. Plants imbibe it for their nutrition and growth, the carbon being retained and the oxygen given out.
 Carbonic oxide Chem., a colorless gas, CO, of a light odor, called more correctly carbon monoxide. It is almost the only definitely known compound in which carbon seems to be divalent. It is a product of the incomplete combustion of carbon, and is an abundant constituent of water gas. It is fatal to animal life, extinguishes combustion, and burns with a pale blue flame, forming carbon dioxide.
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 Choke damp See Carbonic acid, under Carbonic.
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 Damp n.
 1. Moisture; humidity; fog; fogginess; vapor.
 Night . . . with black air
 Accompanied, with damps and dreadful gloom.   --Milton.
 2. Dejection; depression; cloud of the mind.
 Even now, while thus I stand blest in thy presence,
 A secret damp of grief comes o'er my soul.   --Addison.
    It must have thrown a damp over your autumn excursion.   --J. D. Forbes.
 3. Mining A gaseous product, formed in coal mines, old wells, pints, etc.
 Choke damp, a damp consisting principally of carbonic acid gas; -- so called from its extinguishing flame and animal life. See Carbonic acid, under Carbonic.
 Damp sheet, a curtain in a mine gallery to direct air currents and prevent accumulation of gas.
 Fire damp, a damp consisting chiefly of light carbureted hydrogen; -- so called from its tendence to explode when mixed with atmospheric air and brought into contact with flame.
 Di·ox·ide n.  Chem. (a) An oxide containing two atoms of oxygen in each molecule; binoxide. (b) An oxide containing but one atom or equivalent of oxygen to two of a metal; a suboxide. [Obs.]
 Carbon dioxide. See Carbonic acid, under Carbonic.
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 Fixed a.
 1. Securely placed or fastened; settled; established; firm; imovable; unalterable.
 2. Chem. Stable; non-volatile.
 Fixed air Old Chem., carbonic acid or carbon dioxide; -- so called by Dr. Black because it can be absorbed or fixed by strong bases. See Carbonic acid, under Carbonic.
 Fixed alkali Old Chem., a non-volatile base, as soda, or potash, in distinction from the volatile alkali ammonia.
 Fixed ammunition Mil., a projectile and powder inclosed together in a case ready for loading.
 Fixed battery Mil., a battery which contains heavy guns and mortars intended to remain stationary; -- distinguished from movable battery.
 Fixed bodies, those which can not be volatilized or separated by a common menstruum, without great difficulty, as gold, platinum, lime, etc.
 Fixed capital. See the Note under Capital, n., 4.
 Fixed fact, a well established fact. [Colloq.]
 Fixed light, one which emits constant beams; -- distinguished from a flashing, revolving, or intermittent light.
 Fixed oils Chem., non-volatile, oily substances, as stearine and olein, which leave a permanent greasy stain, and which can not be distilled unchanged; -- distinguished from volatile or essential oils.
 Fixed pivot Mil., the fixed point about which any line of troops wheels.
 Fixed stars Astron., such stars as always retain nearly the same apparent position and distance with respect to each other, thus distinguished from planets and comets.
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 carbonic acid
      n : a weak acid known only in solution; formed when carbon
          dioxide combines with water