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Graphite, named by Abraham Gottlob Werner in 1789, from the Greek γράφειν (graphein, "to draw/write", for its use in pencils) is one of the most common allotropes of carbon. Unlike diamond, graphite is an electrical conductor. Thus, it can be used in, for instance, electrical arc lamp electrodes.
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in crystalline structure.. Allotropy or allotropism (from Ancient Greek ἄλλος (allos) ' other ' and τρόπος (tropos) ' manner, form ') is the property of some chemical elements to exist in two or more different forms, in the same physical state, known as allotropes of the elements.
Above the graphite–diamond–liquid carbon triple point, the melting point of diamond increases slowly with increasing pressure; but at pressures of hundreds of GPa, it decreases. [14] At high pressures, silicon and germanium have a BC8 body-centered cubic crystal structure, and a similar structure is predicted for carbon at high pressures.
Diamond and graphite are two allotropes of carbon: pure forms of the same element that differ in structure. If heated over 700 °C (1,292 °F) in air, diamond, being a form of carbon, oxidizes and its surface blackens, but the surface can be restored by re-polishing. [47]
The three relatively well-known allotropes of carbon are amorphous carbon, graphite, and diamond. Once considered exotic, fullerenes are nowadays commonly synthesized and used in research; they include buckyballs , [ 31 ] [ 32 ] carbon nanotubes , [ 33 ] carbon nanobuds [ 34 ] and nanofibers .
Graphite output in 2005 World graphite reserves and mine production in 2022. Graphite is mined by both open pit and underground methods. Graphite usually needs beneficiation. This may be carried out by hand-picking the pieces of gangue (rock) and hand-screening the product or by crushing the rock and floating out the graphite.
Lonsdaleite (named in honour of Kathleen Lonsdale), also called hexagonal diamond in reference to the crystal structure, is an allotrope of carbon with a hexagonal lattice, as opposed to the cubical lattice of conventional diamond.
In mineralogy, amorphous carbon is the name used for coal, carbide-derived carbon, and other impure forms of carbon that are neither graphite nor diamond. In a crystallographic sense, however, the materials are not truly amorphous but rather polycrystalline materials of graphite or diamond [2] within an amorphous carbon matrix. Commercial ...