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clear (diamond) & black (graphite)

Spectral lines o Carbon
General properties
Name, seembol, nummer carbon, C, 6
Pronunciation /ˈkɑrbən/
Element category nonmetal
Group, period, block 14, 2, p
Staundart atomic wicht 12.011(1)
Electron confeeguration [He] 2s2 2p2
2, 4
Electron shells of carbon (2, 4)
Discovery Egyptians an Sumerians[1] (3750 BC)
Recognized as an element bi Antoine Lavoisier[2] (1789)
Physical properties
Phase solid
Density (near r.t.) amorphous:[3] 1.8–2.1 g·cm−3
Density (near r.t.) diamond: 3.515 g·cm−3
Density (near r.t.) graphite: 2.267 g·cm−3
Sublimation pynt 3915 K, 3642 °C, 6588 °F
Triple pynt 4600 K (4327°C), 10800[4][5] kPa
Heat o fusion 117 (graphite) kJ·mol−1
Molar heat capacity 6.155 (diamond)
8.517 (graphite) J·mol−1·K−1
Atomic properties
Oxidation states 4, 3[6], 2, 1[7], 0, −1, −2, −3, −4[8]
Electronegativity 2.55 (Pauling scale)
Ionization energies
1st: 1086.5 kJ·mol−1
2nt: 2352.6 kJ·mol−1
3rd: 4620.5 kJ·mol−1
Covalent radius 77(sp³), 73(sp²), 69(sp) pm
Van der Waals radius 170 pm
Crystal structure diamond
Carbon has a diamond crystal structure

(diamond, clear)
simple hexagonal
Carbon has a Simple Hexagonal crystal structure

(graphite, black)
Magnetic orderin diamagnetic[9]
Thermal conductivity 900-2300 (diamond)
119-165 (graphite) W·m−1·K−1
Thermal expansion (25 °C) 0.8 (diamond)[10] µm·m−1·K−1
Speed of sound (thin rod) (20 °C) 18350 (diamond) m·s−1
Young's modulus 1050 (diamond)[10] GPa
Shear modulus 478 (diamond)[10] GPa
Bulk modulus 442 (diamond)[10] GPa
Poisson ratio 0.1 (diamond)[10]
Mohs hairdness 10 (diamond)
1-2 (graphite)
CAS registry nummer 7440-44-0
Most stable isotopes
Main article: Isotopes o carbon
iso NA hauf-life DM DE (MeV) DP
11C syn 20 min β+ 0.96 11B
12C 98.9% 12C is stable wi 6 neutrons
13C 1.1% 13C is stable wi 7 neutrons
14C trace 5730 y β 0.15 0 14N
· r

Carbon (frae Laitin: carbo "coal") is the chemical element wi seembol C an atomic nummer 6. As a member o group 14 on the periodic table, it is nonmetallic an tetravalent—makin fower electrons available tae furm covalent chemical bonds. Thare are three naiturally occurrin isotopes, wi 12C an 13C bein stable, while 14C is radioactive, decayin wi a hauf-life o aboot 5,730 years.[11] Carbon is ane o the few elements kent syne antiquity.[12]

Thare are several allotropes o carbon o which the baist kent are graphite, diamond, an amorphous carbon.[13] The pheesical properties o carbon vary widely wi the allotropic furm. For example, diamond is heichly transparent, while graphite is opaque an black. Diamond is the hairdest naiturally-occurrin material kent, while graphite is saft enough tae furm a streak on paper (hence its name, frae the Greek wird "γράφω" which means "tae write"). Diamond haes a very law electrical conductivity, while graphite is a very guid conductor. Unner normal condeetions, diamond, carbon nanotube an graphene hae the heichest thermal conductivities o aw kent materials.

Aw carbon allotropes are solids unner normal condeetions wi graphite bein the maist thermodynamically stable furm. Thay are chemically resistant an require heich temperatur tae react even wi oxygen. The maist common oxidation state o carbon in inorganic compounds is +4, while +2 is foond in carbon monoxide an ither transeetion metal carbonyl complexes. The lairgest soorces o inorganic carbon are limestanes, dolomites an carbon dioxide, but signeeficant quantities occur in organic deposits o coal, peat, ile an methane clathrates. Carbon furms mair compoonds than ony ither element, wi almaist ten million pure organic compoonds describit tae date, which in turn are a tiny fraction o such compoonds that are theoretically possible unner staundart condeetions.[14]

Carbon is the 15t maist abundant element in the Yird's crust, an the fowert maist abundant element in the universe bi mass efter hydrogen, helium, an oxygen. It is present in aw kent life furms, an in the human body carbon is the seicont maist abundant element bi mass (aboot 18.5%) efter oxygen.[15] This abundance, thegither wi the unique diversity o organic compoonds an thair unuisual polymer-furmin ability at the temperaturs commonly encoontered on Yird, mak this element the chemical basis o aw kent life.

References[eedit | eedit soorce]

  1. "History of Carbon and Carbon Materials - Center for Applied Energy Research - University of Kentucky". Retrieved 2008-09-12. 
  2. Senese, Fred (200-09-09). "Who discovered carbon?". Frostburg State University. Retrieved 2007-11-24.  Check date values in: |date= (help)
  3. Lide, D. R., ed. (2005). CRC Handbook of Chemistry and Physics (86th ed.). Boca Raton (FL): CRC Press. ISBN 0-8493-0486-5. 
  4. Haaland, D (1976). "Graphite-liquid-vapor triple point pressure and the density of liquid carbon". Carbon 14 (6): 357. doi:10.1016/0008-6223(76)90010-5. 
  5. Savvatimskiy, A (2005). "Measurements of the melting point of graphite and the properties of liquid carbon (a review for 1963–2003)". Carbon 43 (6): 1115. doi:10.1016/j.carbon.2004.12.027. 
  6. "Fourier Transform Spectroscopy of the System of CP". Retrieved 2007-12-06. 
  7. "Fourier Transform Spectroscopy of the Electronic Transition of the Jet-Cooled CCI Free Radical". Retrieved 2007-12-06. 
  8. "Carbon: Binary compounds". Retrieved 2007-12-06. 
  9. Magnetic susceptibility of the elements and inorganic compounds, in Handbook of Chemistry and Physics 81st edition, CRC press.
  10. 10.0 10.1 10.2 10.3 10.4 Properties of diamond, Ioffe Institute Database
  11. "Carbon – Naturally occurring isotopes". WebElements Periodic Table. Retrieved 2008-10-09. 
  12. "History of Carbon". Retrieved 2013-01-10. 
  13. "World of Carbon – Interactive Nano-visulisation in Science & Engineering Education (IN-VSEE)". Retrieved 2008-10-09. 
  14. Chemistry Operations (December 15, 2003). "Carbon". Los Alamos National Laboratory. Archived from the original on 2008-09-13. Retrieved 2008-10-09. 
  15. "Biological Abundance of Elements". The Internet Encyclopedia of Science. Retrieved 2008-10-09. 

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