occurs in many forms including diamonds to graphite?
472906
Carbon. A diamond is carbon put under a lot of pressure. And haven't you ever heard of somebody drawing with "opaper and carbons"?
938225
a compound contaning carbon
11244
All are true except that each atom is bonded to four others.  Carbon's valence is four, and so it can only form four bonds--by having double bonds, there is no room to bond to four atoms.  Diamond, on the other hand, has each carbon atom bonded to four other atoms, but no double bonds.\n\nGraphite forms in sheets, with no covalent linking between pifferent sheets.  That is why it is so soft.\n\nthe picture on the second link does not show the double bonds, but if you pick a single direction and regard all parallel bonds in that direction to be double bonds, the valence states will make sense.
1121811
Neither. Allotropes are different forms of a pure element.\n\nFor example, both graphite and diamond are pure carbon. They differ in the way the carbon atoms are bonded to each other, which gives them different physical properties.\n\nSince there is only one element present, allotropes cannot be compounds. Since there are not multiple compounds present, allotropes also cannot be mixtures.
330145
Solid and in solids Diamond.\n\nSecond  Alummina and titanium carbide.
804135
diamonds are made of carbon.\nA diamond is a transparent crystal of tetrahedrally bonded carbon atoms. Diamonds have been adapted for many uses because of the material's exceptional physical characteristics. Most notable are its extreme hardness of diamond, its high dispersion index, and high thermal conductivity.\n\nThere form under extreme heat and pressure.\nDiamonds are formed by prolonged exposure of carbon bearing materials to high pressure and temperature. On Earth, the formation of diamonds is possible because there are regions deep within the Earth that are at a high enough pressure and temperature that the formation of diamonds is thermodynamically favorable. Under continental crust, diamonds form starting at depths of about 150 kilometers (90 miles), where pressure is roughly 5 gigapascals and the temperature is around 1200 degrees Celsius (2200 degrees Fahrenheit).\n\nWhere are they found?\nHistorically diamonds were known to be found only in alluvial deposits in southern India; India led the world in diamond production from the time of their discovery in approximately the 9th century BCE to the mid-18th century CE, but the commercial potential of these sources has been exhausted. The first non-Indian diamond source was found in Brazil in 1725. While no commercial diamond production exists in the US, Arkansas is the only state to have a verifiable source of diamonds. Today, most commercially viable diamond deposits are in Africa, notably in South Africa, Namibia, Botswana, the Democratic Republic of Congo, Angola, Tanzania and Sierra Leone [5]. There are also commercial deposits being actively mined in the Northwest Territories of Canada, Siberia (mostly in Yakutia territory, for example Mir pipe and Udachnaya pipe), Brazil, and in Northern and Western Australia. Diamond prospectors continue to search the globe for diamond-bearing kimberlite and lamproite pipes.\n\nWhat are they used for?\nThe dominant industrial use of diamond is in cutting, drilling, grinding, and polishing. Most uses of diamonds in these technologies do not require large diamonds; in fact, most diamonds that are gem-quality except for their small size, can find an industrial use. Diamonds are embedded in drill tips or saw blades, or ground into a powder for use in grinding and polishing applications. Specialized applications include use in laboratories as containment for high pressure experiments (see diamond anvil), high-performance bearings, and limited use in specialized windows.
872414
Diamonds are formed by intense pressure on carbon deposits in the Earth's surface.  With enough pressure and time, a chunk of carbon can form a diamond.  The carbon that is in the Earth's surface can come from fossilized organic materials (ie prehistoric plants, animals, etc).
965654
I would have said Diamonds but I just found this from physicsweb.org:\n\n    Diamonds are not forever\n\n    Physicists in Germany have created a material that is harder than diamond. Natalia Dubrovinskaia and colleagues at the University of Bayreuth made the new material by subjecting carbon-60 molecules to immense pressures. The new form of carbon, which is known as aggregated diamond nanorods, is expected to have many industrial applications (App. Phys. Lett. 87 083106).\n\n    The hardness of a material is measured by its isothermal bulk modulus. Aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), compared with 442 GPa for conventional diamond. Dubrovinskaia and two of her co-workers - Leonid Dubrovinky and Falko Langenhorst - have patented the process used to make the new material.\n\n    Diamond derives its hardness from the fact that each carbon atom is connected to four other atoms by strong covalent bonds. The new material is different in that it is made of tiny interlocking diamond rods. Each rod is a crystal that has a diameter of between 5 and 20 nanometres and a length of about 1 micron.
297283
Not pure carbon in pure water, no.  Don't believe me, try sticking a pencil lead (graphite is pure carbon, not actually lead) into a glass of water and see if it dissolves.\n\nBut carbon will dissolve in some solutions.\n\nAs an aside, you think the guy above me might be trying too hard?  A more concise answer is usually preferable.
523511
This same question was asked earlier this week.\n\nThe short answer is that all sorts of things can destroy diamond, anything from a rock to a saw to some acids.
523994
Once carbon is turned into a diamond (which takes a VERY long time), it cannot be changed back. Well, it could, but the energy required is enormous.  Remember, diamonds are one of the hardest substances on the planet.
44241
Yes, you can. Let me give you more details: Diamonds melt approximately between 7,000 and 8,000 Kelvin degrees.\nSee http://www.comppub.com/publ/ICCN2002/298.pdf (page 2, top right):\n"Changes in energy and atomic number density of Fig. 2 definitely show that the melting of diamond lattice occurred between 7,000 and 8,000K. apparently at 10.000 Kelvin degrees. "\n\nAnother possibility is to heat the diamond at very high pressures (up to 30 GPa.) using a laser beam.\nHave a look at http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APCPCS000309000001000651000001&idtype=cvips&gifs=yes\n\nHope this helps.\nCheers,\nalphabravotango
62079
Yes, diamond, graphite, and its relatives are all inorganic. A more specific definition of an organic compound is something that contains both carbon and hydrogen atoms.
794460
Diamonds are not forever\n\nPhysicists in Germany have created a material that is harder than diamond. Natalia Dubrovinskaia and colleagues at the University of Bayreuth made the new material by subjecting carbon-60 molecules to immense pressures. The new form of carbon, which is known as aggregated diamond nanorods, is expected to have many industrial applications (App. Phys. Lett. 87 083106).\n\nThe hardness of a material is measured by its isothermal bulk modulus. Aggregated diamond nanorods have a modulus of 491 gigapascals (GPa), compared with 442 GPa for conventional diamond. Dubrovinskaia and two of her co-workers - Leonid Dubrovinky and Falko Langenhorst - have patented the process used to make the new material.\n\nDiamond derives its hardness from the fact that each carbon atom is connected to four other atoms by strong covalent bonds. The new material is different in that it is made of tiny interlocking diamond rods. Each rod is a crystal that has a diameter of between 5 and 20 nanometres and a length of about 1 micron.
353876
If by "naturally occuring" you mean present in nature in its elemental form, then the answer includes noble gases (Helium and Argon), noble metals (Gold and Platinum and maybe Copper), and some diatomic molecules (Oxygen, Nitrogen) as well as Sulfur (S_8) and Carbon (graphite and diamond).  Most of the metals are found as some kind of oxide (in ores) or in salts (sodium chloride).  The halogens are found in salts (sodium chloride). \n\nA lot of today's useful materials were never present in significant amounts in elemental form, for example: iron, aluminum, zinc.
842652
Based on this information, no, a diamond will not spontaneously decompose into graphite. It also does not imply that diamonds will last forever. It only states that diamonds are a better carbon based energy source than graphite.
137741
Yes, but it is a very hard thing to do. It's necessary at least 4,500°C to reach the Carbon melting point. \nSome scientists, especially from the Lawrence Livermore National Laboratory, says it's possible to have two kinds of liquid Carbon instead of only one. Considering that that are Carbon in two kinds at solid states: Diamond and Graphite, it makes sense.