Carbon

(karbon.) [L. carbo.] (Chem.) A very abundant non-metallic element, occurring in three forms, crystallized and transparent as the diamond (q.v.), crystalline and opaque as graphite (q. v.), and opaque or amorphous as charcoal (q. v.) C. is a nece ary constituent of all organic or organized compounds. At the ordinary temperature, C. scarcely shows any chemical affinity, but at ahigh temperature it unites with oxygen, with incandescence and great evolution of light and heat, forming carbonic acid, or, when the carbon is in exce , carbonic oxide. At. weight 12; Symbol C.-Carbonic acid is a colorle gas, which maybe liquefied by a pre ure of 36 atmospheres at 320, and solidified by a still greater reduction of temperature. In the gaseous state, its sp. gr. is 1.52, owing to which it may with ease be poured from one ve el into another, like water. It is a normal constituent of the atmosphere. It is a non-supporter of ordinary combustion; will not support life, and in an impure state is the choke dump of miners. Water di olves about its own bulk at the ordinary temperature; vegetation decomposes it with separation of free oxygen. It po e es acrid properties, and unites with bases to form salts. Form. CO2. Carbonates are decomposed by almost every acid with evolution of gaseous carbonic acid. The most important carbonates are: Carbonate of Calcium, which occurs abundantly in nature as limestone, chalk, calc spar, and marble. It is also a principal constituent of egg and mollusc shells. Artificially prepared, it is a white powder, insoluble in water. At a red heat it is converted into caustic lime. Carbonate of Lead is extensively used in commerce as White Lead. Carbonate of Magnesium occurs native as Magnesite, and also in the hydrated form in a white amorphous substance insoluble in water, known in commerce as Magnesia alba. It is a very light, bulky, insoluble powder, extensively used as a purgative. Carbonate of Pota ium, known also as Pearl-ash, crystallizes in the hydrated state in rhombic octahedra, which are cry soluble in water. The solution has a strong alkaline taste; when saturated with carbonic acid, it is converted into Bi-carbonate of Pota ium, which crystallizes in rhomboidal prisms, much le soluble than the neutral carbonate. Carbonate of Sodium is manufactured in commerce in enormous quantities, and is ordinarily known as Soda. See SODIUM.- Carbon is Oxide is a colorle gas, perfectly neutral, insoluble in water, and very poisonous when inhaled. It does not support combustion, but when ignited in the air burns with a lambent blue flame, producing carbonic acid. At a high temperature it acts as a strong reducing agent. Sp. gr. 0.96; Form. CO. Carbon, an E. co. of Pennsylvania, b. S.E. by the Blue Mts., and traversed by the Lehigh river. Its name is derived from the vast beds of anthracite coal which are mined within its limits. Area, 400 sq.m. C. Mauch Chunk. Pop. 28,144. [s. 144]