Carbon

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Carbon (pronounced /ˈkɑrbən/) is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, with 12C and 13C being stable, while 14C is radioactive, decaying with a half-life of about 5730 years. Carbon is one of the few elements known since antiquity. The name "carbon" comes from Latin language carbo, coal, and, in some Romance and Slavic languages, the word carbon can refer both to the element and to coal.

There are several allotropes of carbon of which the best known are graphite, diamond, and amorphous carbon. The physical properties of carbon vary widely with the allotropic form. For example, diamond is highly transparent, while graphite is opaque and black. Diamond is among the hardest materials known, while graphite is soft enough to form a streak on paper (hence its name, from the Greek word "to write"). Diamond has a very low electrical conductivity, while graphite is a very good conductor. Under normal conditions, diamond has the highest thermal conductivity of all known materials. All the allotropic forms are solids under normal conditions but graphite is the most thermodynamically stable.

All forms of carbon are highly stable, requiring high temperature to react even with oxygen. The most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and other transition metal carbonyl complexes. The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil and methane clathrates. Carbon forms more compounds than any other element, with almost ten million pure organic compounds described to date, which in turn are a tiny fraction of such compounds that are theoretically possible under standard conditions.

Carbon is one of the least abundant elements in the Earth's crust, but the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. It is present in all known lifeforms, and in the human body carbon is the second most abundant element by mass (about 18.5%) after oxygen. This abundance, together with the unique diversity of organic compounds and their unusual polymer-forming ability at the temperatures commonly encountered on Earth, make this element the chemical basis of all known life.

For more information about Carbon, read the full article at Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.


News tagged with carbon atoms

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How Perfect Can Graphene Be?

How Perfect Can Graphene Be?

Nanotechnology / Nanomaterials

created Oct 13, 2009 | popularity 4.6 / 5 (30) | comments 5

(PhysOrg.com) -- Physicists have investigated the purest graphene to date, and have found that the material possesses unprecedented high electronic quality. The discovery has raised the bar for this relatively ...


Engineering Carbon for Impressive Hydrogen Storage

Nanotechnology / Nanomaterials

created May 22, 2009 | popularity 4 / 5 (16) | comments 14

(PhysOrg.com) -- University of Missouri researchers recently showed how carbon nanostructures can be engineered to become excellent media for hydrogen storage, work that may be important for the advancement of hydrogen-energy ...


New study confirms exotic electric properties of graphene

New study confirms exotic electric properties of graphene

Nanotechnology / Nanomaterials

created Nov 17, 2009 | popularity 4.8 / 5 (23) | comments 1

(PhysOrg.com) -- First, it was the soccer-ball-shaped molecules dubbed buckyballs. Then it was the cylindrically shaped nanotubes. Now, the hottest new material in physics and nanotechnology is graphene: ...


Researchers invent new method for graphene growth

Researchers invent new method for graphene growth

Nanotechnology / Nanomaterials

created Nov 10, 2009 | popularity 4.9 / 5 (22) | comments 0

(PhysOrg.com) -- A Cornell research team has invented a simple way to make graphene electrical devices by growing the graphene directly onto a silicon wafer.


Researchers make key step towards turning methane gas into liquid fuel

Chemistry / Materials Science

created Oct 22, 2009 | popularity 3.5 / 5 (8) | comments 1

(PhysOrg.com) -- Researchers at the University of Washington and the University of North Carolina at Chapel Hill have taken an important step in converting methane gas to a liquid, potentially making it more useful as a fuel ...


Physicists discover novel electronic properties in two-dimensional carbon structure

Nanotechnology / Nanophysics

created Oct 14, 2009 | popularity 4.8 / 5 (11) | comments 1

Rutgers researchers have discovered novel electronic properties in two-dimensional sheets of carbon atoms called graphene that could one day be the heart of speedy and powerful electronic devices.


Graphite mimics iron's magnetism

Graphite mimics iron's magnetism

Nanotechnology / Nanophysics

created Oct 04, 2009 | popularity 4.6 / 5 (17) | comments 1

Researchers of Eindhoven University of Technology and the Radboud University Nijmegen in The Netherlands show for the first time why ordinary graphite is a permanent magnet at room temperature. The results ...


Cheap, sensitive sensors could detect explosives, toxins in water

Cheap, sensitive sensors could detect explosives, toxins in water

Nanotechnology / Nanophysics

created Sep 24, 2009 | popularity 4 / 5 (3) | comments 0

(PhysOrg.com) -- A sensitive new Stanford-developed disposable chip detects low concentrations of the explosive trinitrotoluene (TNT) and a close chemical cousin of the dreaded toxic nerve agent sarin in water ...


Diamonds may be the ultimate MRI probe, say Quantum physicists

Diamonds May Be the Ultimate MRI Probe, Say Quantum Physicists

Physics / Quantum Physics

created Sep 22, 2009 | popularity 4.5 / 5 (11) | comments 1

(PhysOrg.com) -- Diamonds, it has long been said, are a girl's best friend. But a research team including a physicist from the National Institute of Standards and Technology has recently found that the gems ...


Carbon nanoballs as data storage units

Carbon nanoballs as data storage units

Nanotechnology / Nanophysics

created Sep 01, 2009 | popularity 4.8 / 5 (36) | comments 4

Small, smaller, "nano" data storage! Interest is growing in the use of metallofullerenes - carbon “cages” with embedded metallic compounds - as materials for miniature data storage devices. Researchers at ...


ibm pentacene

Scientists Image the 'Anatomy' of a Molecule (w/ Video)

Nanotechnology / Nanophysics

created Aug 28, 2009 | popularity 4.8 / 5 (43) | comments 4

(PhysOrg.com) -- For the first time, IBM researchers in Zurich, Switzerland, have taken a 3D image of an individual molecule. Using an atomic force microscope, the researchers constructed a "force map" of ...


Video shows nanotube spins as it grows

Video shows nanotube spins as it grows (w/ Videos)

Nanotechnology / Nanomaterials

created Jul 27, 2009 | popularity 4.8 / 5 (9) | comments 6

(PhysOrg.com) -- New video showing the atom-by-atom growth of carbon nanotubes reveals they rotate as they grow, much like the halting motion of a mechanical clock's second hand. Published online this month ...


Material world: Graphene's versatility promises new applications

Graphene's versatility promises new applications

Nanotechnology / Nanomaterials

created Jul 09, 2009 | popularity 5 / 5 (6) | comments 1

Since its discovery just a few years ago, graphene has climbed to the top of the heap of new super-materials poised to transform the electronics and nanotechnology landscape. As N.J. Tao, a researcher at the ...


Graphene Yields Secrets to Its Extraordinary Properties

Graphene Yields Secrets to Its Extraordinary Properties

Nanotechnology / Nanophysics

created May 14, 2009 | popularity 4.8 / 5 (25) | comments 0

(PhysOrg.com) -- Applying innovative measurement techniques, researchers from the Georgia Institute of Technology and the National Institute of Standards and Technology have directly measured the unusual energy ...


Researchers develop new method for producing transparent conductors

Nanotechnology / Nanomaterials

created May 13, 2009 | popularity 5 / 5 (7) | comments 2

(PhysOrg.com) -- Researchers at UCLA have developed a new method for producing a hybrid graphene-carbon nanotube, or G-CNT, for potential use as a transparent conductor in solar cells and consumer electronic devices. These ...