but as most compounds with multiple single-bonded oxygens on a single carbon it is unstable. [92] Through this intermediate, though, resonance-stabilized carbonate ions are produced. Some important minerals are carbonates, notably calcite. Carbon disulfide ( CS

Anderson D. J.; Rosenfeld, R. N. (1991). "Photodissociation of Carbon Suboxide". Journal of Chemical Physics. 94 (12): 7852–7867. Bibcode: 1991JChPh..94.7857A. doi: 10.1063/1.460121. Shungite is solely obtainable from the village of Shunga in Russia and is typically extracted through manual methods rather than industrial ones. Where Should I Place My Shungite? The great variety of carbon compounds include such lethal poisons as tetrodotoxin, the lectin ricin from seeds of the castor oil plant Ricinus communis, cyanide (CN −), and carbon monoxide; and such essentials to life as glucose and protein. In nuclear applications where graphite is used as a neutron moderator, accumulation of Wigner energy followed by a sudden, spontaneous release may occur. Annealing to at least 250°C can release the energy safely, although in the Windscale fire the procedure went wrong, causing other reactor materials to combust.In combination with oxygen in carbon dioxide, carbon is found in the Earth's atmosphere (approximately 900gigatonnes of carbon — each ppm corresponds to 2.13Gt) and dissolved in all water bodies (approximately 36,000gigatonnes of carbon). Carbon in the biosphere has been estimated at 550gigatonnes but with a large uncertainty, due mostly to a huge uncertainty in the amount of terrestrial deep subsurface bacteria. [56] Hydrocarbons (such as coal, petroleum, and natural gas) contain carbon as well. Coal "reserves" (not "resources") amount to around 900gigatonnes with perhaps 18,000 Gt of resources. [57] Oil reserves are around 150gigatonnes. Proven sources of natural gas are about 175 ×10 12cubic metres (containing about 105 gigatonnes of carbon), but studies estimate another 900 ×10 12cubic metres of "unconventional" deposits such as shale gas, representing about 540 gigatonnes of carbon. [58] Unlike precious metals such as gold or platinum, gem diamonds do not trade as a commodity: there is a substantial mark-up in the sale of diamonds, and there is not a very active market for resale of diamonds. Some allotropes of carbon: a) diamond; b) graphite; c) lonsdaleite; d–f) fullerenes (C 60, C 540, C 70); g) amorphous carbon; h) carbon nanotube

Itzhaki, Lior; Altus, Eli; Basch, Harold; Hoz, Shmaryahu (2005). "Harder than diamond: Determining the cross-sectional area and Young's modulus of molecular rods". Angew. Chem. Int. Ed. 44 (45): 7432–7435. doi: 10.1002/anie.200502448. PMID 16240306. Nusinovich, G. S. (2004). Introduction to the physics of gyrotrons. JHU Press. p.229. ISBN 978-0-8018-7921-0. Diamond is an excellent electrical insulator, [28] and has the highest breakdown electric field of any known material.Ferchault de Réaumur, R.-A. (1722). L'art de convertir le fer forgé en acier, et l'art d'adoucir le fer fondu, ou de faire des ouvrages de fer fondu aussi finis que le fer forgé (English translation from 1956). Paris, Chicago. Use query for carbon-8". barwinski.net. Archived from the original on 2005-02-07 . Retrieved 2007-12-21. Dienwiebel, Martin; Verhoeven, Gertjan; Pradeep, Namboodiri; Frenken, Joost; Heimberg, Jennifer; Zandbergen, Henny (2004). "Superlubricity of Graphite" (PDF). Physical Review Letters. 92 (12): 126101. Bibcode: 2004PhRvL..92l6101D. doi: 10.1103/PhysRevLett.92.126101. PMID 15089689. S2CID 26811802. Archived (PDF) from the original on 2011-09-17.

Harlow, G. E. (1998). The nature of diamonds. Cambridge University Press. p.223. ISBN 978-0-521-62935-5. The reactants are the metal oxide compound and carbon. The products are the pure metal and either carbon monoxide or carbon dioxide. Isotopes of carbon are atomic nuclei that contain six protons plus a number of neutrons (varying from 2 to 16). Carbon has two stable, naturally occurring isotopes. [16] The isotope carbon-12 ( 12C) forms 98.93% of the carbon on Earth, while carbon-13 ( 13C) forms the remaining 1.07%. [16] The concentration of 12C is further increased in biological materials because biochemical reactions discriminate against 13C. [68] In 1961, the International Union of Pure and Applied Chemistry (IUPAC) adopted the isotope carbon-12 as the basis for atomic weights. [69] Identification of carbon in nuclear magnetic resonance (NMR) experiments is done with the isotope 13C.a b Dresselhaus, M. S.; Dresselhaus, G.; Avouris, Ph., eds. (2001). Carbon nanotubes: synthesis, structures, properties and applications. Topics in Applied Physics. Vol.80. Berlin: Springer. ISBN 978-3-540-41086-7.