|1.||a. a nonmetallic element existing in the three crystalline forms: graphite, diamond, and buckminsterfullerene: occurring in carbon dioxide, coal, oil, and all organic compounds. The isotope carbon-12 has been adopted as the standard for atomic wt; carbon-14, a radioisotope with a half-life of 5700 years, is used in radiocarbon dating and as a tracer. Symbol: C; atomic no: 6; atomic wt: 12.011; valency: 2, 3, or 4; relative density: 1.8--2.1 (amorphous), 1.9--2.3 (graphite), 3.15--3.53 (diamond); sublimes at 3367±25°C; boiling pt: 4827°C|
|b. (as modifier): a carbon compound|
|2.||carbon paper short for carbon copy|
|3.||a carbon electrode used in a carbon-arc light or in carbon-arc welding|
|4.||a rod or plate, made of carbon, used in some types of battery|
|[C18: from French carbone, from Latin carbō charcoal, dead or glowing coal]|
carbon car·bon (kär'bən)
A nonmetallic element occuring in many inorganic and in all organic compounds, existing as graphite and diamond and as a constituent of coal, limestone, and petroleum, and capable of chemical self-bonding to form a number of important molecules. Atomic number 6; atomic weight 12.01115; sublimation point above 3,500°C; melting point 3,550°C; specific gravity of amorphous carbon 1.8 to 2.1, of diamond 3.15 to 3.53, of graphite 1.9 to 2.3; valence 2, 3, 4.
|carbon (kär'bən) Pronunciation Key
A naturally abundant, nonmetallic element that occurs in all organic compounds and can be found in all known forms of life. Diamonds and graphite are pure forms, and carbon is a major constituent of coal, petroleum, and natural gas. Carbon generally forms four covalent bonds with other atoms in larger molecules. Atomic number 6; atomic weight 12.011; sublimation point above 3,500°C; boiling point 4,827°C; specific gravity of amorphous carbon 1.8 to 2.1, of diamond 3.15 to 3.53, of graphite 1.9 to 2.3; valence 2, 3, 4. See Periodic Table.
county, eastern Pennsylvania, U.S., flanked to the north by the Pocono Mountains and to the south by Blue Mountain and located midway between the cities of Wilkes-Barre and Allentown. It consists of a mountainous region lying largely in the Appalachian Ridge and Valley physiographic province. The principal waterways are the Lehigh River and Tobyhanna, Quakake, Nesquehoning, Mahoning, Lizard, and Aquashicola creeks, as well as Penn Forest and Wild Creek reservoirs. State parks include Hickory Run, Lehigh Gorge, and Beltzville, which surrounds Beltzville Lake. The Appalachian National Scenic Trail follows the ridgeline of Blue Mountain
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