Carbon (C)
nonmetalSolid
Peso atomico standard
12,011 u [12,0096, 12,0116]Configurazione elettronica
[He] 2s2 2p2Punto di fusione
3549,85 °CPunto di ebollizione
3824,85 °CDensità
2267 kg/m³Stati di ossidazione
−4, −3, −2, −1, 0, +1, +2, +3, +4Elettronegatività (Pauling)
2,55Energia di ionizzazione (1ª)
11,260288 eVAnno della scoperta
1797Raggio atomico
70 pmDettagli
Carbon is a nonmetal in group 14 and the defining element of organic chemistry. Its small atoms form strong covalent bonds with carbon and many other elements, allowing chains, rings, networks, and multiple bonds of great diversity. It occurs naturally as graphite, diamond, amorphous carbon-rich materials, carbonate minerals, fossil carbon, dissolved carbon species, and as a central element in living matter.
Carbon is a member of group 14 of the periodic table. It has three allotropic forms of it, diamonds, graphite and fullerite. Carbon-14 is commonly used in radioactive dating. Carbon occurs in all organic life and is the basis of organic chemistry. Carbon has the interesting chemical property of being able to bond with itself, and a wide variety of other elements.
The name derives from the Latin carbo for "charcoal". It was known in prehistoric times in the form of charcoal and soot. In 1797, the English chemist Smithson Tennant proved that diamond is pure carbon.
Carbon, the sixth most abundant element in the universe, has been known since ancient times. Carbon is most commonly obtained from coal deposits, although it usually must be processed into a form suitable for commercial use. Three naturally occurring allotropes of carbon are known to exist: amorphous, graphite and diamond.
From the Latin word carbo: charcoal. Carbon, an element of prehistoric discovery, is very widely distributed in nature. It is found in abundance in the sun, stars, comets, and atmospheres of most planets. Carbon in the form of microscopic diamonds is found in some meteorites.
Natural diamonds are found in kimberlite of ancient volcanic "pipes," found in South Africa, Arkansas, and elsewhere. Diamonds are now also being recovered from the ocean floor off the Cape of Good Hope. About 30% of all industrial diamonds used in the U.S. are now made synthetically.
The energy of the sun and stars can be attributed at least in part to the well-known carbon-nitrogen cycle.
Pure carbon has several allotropes. Graphite is a soft, black to steel-gray, opaque solid with a metallic luster and layered structure. Diamond is a transparent, very hard crystalline solid when pure, though impurities can color it. Amorphous carbon materials are typically black powders or porous solids.
Graphite is used in electrodes, refractories, lubricants, foundry materials, pencils, brake linings, and lithium-ion battery anodes. Diamond is valued as a gemstone and is used in cutting, grinding, drilling, and heat-spreading applications. Carbon black reinforces rubber and pigments inks, coatings, and plastics. Activated carbon is used for adsorption in water treatment, gas purification, and solvent recovery. Carbon fibers provide high strength and low mass in composites.
Amorphous carbon is formed when a material containing carbon is burned without enough oxygen for it to burn completely. This black soot, also known as lampblack, gas black, channel black or carbon black, is used to make inks, paints and rubber products. It can also be pressed into shapes and is used to form the cores of most dry cell batteries, among other things.
Graphite, one of the softest materials known, is a form of carbon that is primarily used as a lubricant. Although it does occur naturally, most commercial graphite is produced by treating petroleum coke, a black tar residue remaining after the refinement of crude oil, in an oxygen-free oven. Naturally occurring graphite occurs in two forms, alpha and beta. These two forms have identical physical properties but different crystal structures. All artificially produced graphite is of the alpha type. In addition to its use as a lubricant, graphite, in a form known as coke, is used in large amounts in the production of steel. Coke is made by heating soft coal in an oven without allowing oxygen to mix with it. Although commonly called lead, the black material used in pencils is actually graphite.
Diamond, the third naturally occurring form of carbon, is one of the hardest substances known. Although naturally occurring diamond is typically used for jewelry, most commercial quality diamonds are artificially produced. These small diamonds are made by squeezing graphite under high temperatures and pressures for several days or weeks and are primarily used to make things like diamond tipped saw blades. Although they posses very different physical properties, graphite and diamond differ only in their crystal structure.
A fourth allotrope of carbon, known as white carbon, was produced in 1969. It is a transparent material that can split a single beam of light into two beams, a property known as birefringence. Very little is known about this form of carbon.
Large molecules consisting only of carbon, known as buckminsterfullerenes, or buckyballs, have recently been discovered and are currently the subject of much scientific interest. A single buckyball consists of 60 or 70 carbon atoms (C60 or C70) linked together in a structure that looks like a soccer ball. They can trap other atoms within their framework, appear to be capable of withstanding great pressures and have magnetic and superconductive properties.
Carbon-14, a radioactive isotope of carbon with a half-life of 5,730 years, is used to find the age of formerly living things through a process known as radiocarbon dating. The theory behind carbon dating is fairly simple. Scientists know that a small amount of naturally occurring carbon is carbon-14. Although carbon-14 decays into nitrogen-14 through beta decay, the amount of carbon-14 in the environment remains constant because new carbon-14 is always being created in the upper atmosphere by cosmic rays. Living things tend to ingest materials that contain carbon, so the percentage of carbon-14 within living things is the same as the percentage of carbon-14 in the environment. Once an organism dies, it no longer ingests much of anything. The carbon-14 within that organism is no longer replaced and the percentage of carbon-14 begins to decrease as it decays. By measuring the percentage of carbon-14 in the remains of an organism, and by assuming that the natural abundance of carbon-14 has remained constant over time, scientists can estimate when that organism died. For example, if the concentration of carbon-14 in the remains of an organism is half of the natural concentration of carbon-14, a scientist would estimate that the organism died about 5,730 years ago, the half-life of carbon-14.
There are nearly ten million known carbon compounds and an entire branch of chemistry, known as organic chemistry, is devoted to their study. Many carbon compounds are essential for life as we know it. Some of the most common carbon compounds are: carbon dioxide (CO2), carbon monoxide (CO), carbon disulfide (CS2), chloroform (CHCl3), carbon tetrachloride (CCl4), methane (CH4), ethylene (C2H4), acetylene (C2H2), benzene (C6H6), ethyl alcohol (C2H5OH) and acetic acid (CH3COOH).
Isotopes in Biology
Because of above-ground nuclear bomb testing, the neutrons released reacted with CO2 to increase atmospheric 14C via the 14N (n, p) 14C reaction, and 14C started rising in about 1955 (Fig. IUPAC.6.1) and reached a peak in the mid-1960s [59] Q. Hua, M. Barbetti, A. Z. Rakowski. Radiocarbon55, 2059 (2013).. With the curtailment of above-ground nuclear testing in the 1960s, the atmospheric 14C concentration has since been decreasing exponentially (Fig. IUPAC.6.1). This variation in 14C concentration is used to establish when cells in biology were born and how quickly they are renewed [60] K. L. Spalding, R. D. Bhardwaj, B. A. Buchholz, H. Druid, J. Frisén. Cell122, 133 (2005).. This technique is commonly called carbon-14 bomb pulse biology and it has provided information on the age of cells and their regeneration. Figure 4.6.2 shows the average age of selected cells in a 30-year-old human.
Isotopes in Earth/Planetary Science
Because molecules, atoms, and ions of the stable isotopes of carbon possess slightly different physical and chemical properties, they commonly will be fractionated during physical, chemical, and biological processes, giving rise to variations in isotopic abundances and in atomic weights. Carbon in natural terrestrial materials shows a substantial variation in isotopic abundance (Fig. IUPAC.6.3), providing many different ways of distinguishing sources of materials and processes affecting them [13] M. W. Wieser, T. B. Coplen. Pure Appl Chem.83, 359 (2011).. Variations in the isotope-amount ratio n(13C)/n(12C) in tree rings and in CO2 trapped in ice cores have been used to study causes of variations in atmospheric CO2 levels [66] RealClimate. How Do We Know That Recent CO2 Increases Are Due to Human Activities? RealClimate (2014), Feb. 22; http://www.realclimate.org/index.php/archives/2004/12/how-do-we-know-that-recent-cosub2sub-increases-are-due-to-human-activities-updated/.. Variations in the isotope-amount ratio n(13C)/n(12C) and in the 14C concentration of surface ocean waters have been used to trace the incorporation and movement of atmospheric CO2 in the ocean [66] RealClimate. How Do We Know That Recent CO2 Increases Are Due to Human Activities? RealClimate (2014), Feb. 22; http://www.realclimate.org/index.php/archives/2004/12/how-do-we-know-that-recent-cosub2sub-increases-are-due-to-human-activities-updated/..
Isotopes in Forensic Science and Anthropology
Variations in the isotope-amount ratio n(13C)/n(12C) of biological products can be observed using isotope-ratio mass spectrometry (IRMS) to detect adulteration (the addition of inferior ingredients) in honey and other food products.
The isotope-amount ratio n(13C)/n(12C) can fluctuate between carbon sources, for example C3 plants (found in temperate climates and which use atmospheric carbon dioxide to make a 3-carbon molecule during photosynthesis — examples include rice, potatoes, tomatoes, and sugar beets), C4 plants (found in hot climates and which use atmospheric carbon dioxide to make a 4-carbon molecule during photosynthesis — examples include corn and sugar cane), animal carbon, atmospheric CO2, etc. This commonly makes it possible to detect whether these different carbon sources have been mixed by using isotope or mass balance to distinguish, for example, between beet sugar and cane sugar. Complications in source identification can arise with plants that open stomata at night to collect carbon dioxide to use a third mechanism to fix atmospheric carbon dioxide (CAM or crassulacean acid metabolism). The isotope-amount ratio n(13C)/n(12C) of CAM plants overlaps that of C3 or C4 plants — examples include pineapples and jade plants. The following adulterations are commonly detected using stable carbon isotope IRMS:
–Variations in the isotope-amount ratio n(13C)/n(12C) of honey are used to detect the addition (and potential adulteration) of high fructose corn syrup, corn, or sugar cane [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)..
–Variations in the isotope-amount ratio n(13C)/n(12C) of fruit juice have been used to detect the addition of a sugar [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)..
–Variations in the isotope-amount ratio n(13C)/n(12C) of natural vanilla extract have been used to detect the addition of artificial vanillin or p-hydroxybenzaldehyde [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)..
–Variations in the isotope-amount ratio n(13C)/n(12C) of beer are used to detect C4 carbon, which would indicate that a beer company may have added ingredients that are not traditionally used in brewing beer. Therefore, this ratio is used to detect the misrepresentation of a product as being pure [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)., [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002)..
Stable carbon IRMS has been used to determine if the botanical origin of an alcoholic spirit has been mislabeled and if chaptalization (the process of adding sugar to increase the alcoholic content) of wine has occurred [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)., [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002).. 14C scintillation counting has been used to determine the age of wine and alcoholic spirits [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)., [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002).. Variations in the isotope-amount ratio n(13C)/n(12C) of urine has been used to determine if steroids in urine are natural or of synthetic origin. These measurements enable anti-doping laboratories to perfect their methods for detecting steroid doping in athletes [69] B. D. Ahrens, A. W. Butch. Drug Test Anal.5, 534 (2013)., [70] E. Bulska, D. Gorczyca, I. Zalewska, A. Pokrywka, D. Kwiatkowska. J. Pharm. Biomed. Anal.106, 159 (2015)., [71] A. Casilli, T. Piper, F. A. de Oliveira, M. Costa Padilha, H. Marcelo Pereira, M. Thevis, F. R. de Aquino Neto. Drug Test Anal.8, 1204 (2016).. Variations in the isotope-amount ratio n(13C)/n(12C) of marijuana can provide information to determine if the plants were grown “inside” a building or greenhouse or were “open grown” (Fig. IUPAC.6.4). Plant carbon isotopic compositions are controlled by atmospheric CO2 and the supply and demand of CO2 in photosynthesis (the process used by plants to convert light energy from the sun into chemical energy). “Open grown” plants are grown in an area that is well ventilated and receives natural CO2. In contrast, plants grown “inside” receive supplemented CO2 and the photosynthesis process is more confined. Additionally, CO2 from a tank of compressed gas used to augment atmospheric CO2 to increase the growth of marijuana plants is commonly highly depleted in 13C as a refinery by-product. These differences change the carbon isotope ratios of the plants and the ratios vary enough to enable the determination of the growing and cultivation process of marijuana [72] E. K. Shibuya, J. E. Souza Sarkis, O. N. Neto, M. Z. Moreira, R. L. Victoria. Forensic Sci. Int.160, 35 (2006)., [73] J. B. West, J. M. Hurley, J. R. Ehleringer. J Forensic Sci.54, 84 (2009)..
Isotopes in Geochronology
Radioactive 14C is the basis for the radiocarbon dating method to determine the ages of carbon-bearing materials. 14C is formed naturally in the atmosphere by cosmic-ray interactions and was also released by above-ground, nuclear weapons testing (Fig. IUPAC.6.1). Atmospheric 14C is incorporated into plants, animals, soils, groundwater, and ocean water, and it decays with a half-life of ~5700 years. This makes it useful for dating objects, such as archaeological remains and water masses in oceans and aquifers, on time scales ranging from hundreds of years to tens of thousands of years [15] I. D. Clark, P. Fritz. Environmental Isotopes in Hydrogeology, p. 328, Lewis Publishers, New York (1997).. Plants and animals living since the 1950s can be identified by bomb-peak 14C in their cells.
Isotopes in Medicine
14C is used to create isotopically labeled drugs to study their uptake and metabolism in humans [75] J. Peterson, M. McDonell, L. Haroun, F. Monette, R. D. Hildebrand, A. Taboas. Radiological and Chemical Fact Sheets to Support Health Risk Analyses for Contaminated Areas, Prepared by Argonne National Laboratory Environmental Science Division in collaboration with U.S. Department of Energy, Richland Operations Office and Chicago Operations Office (2014), Feb. 22; http://www.remm.nlm.gov/ANL_ContaminantFactSheets_All_070418.pdf., [76] GI & Liver Laboratory at Centre for Liver & Digestive Disorders, The Royal Infirmary of Edinburgh. GI & Liver Laboratory Patient Leaflet., [77] S. L. Kitson. Tracking Human Metabolism with Carbon-14, Drug Discovery and Development (2014), Feb. 23; http://www.dddmag.com/articles/2013/02/tracking-human-metabolism-carbon-14.. 13C is used in breath tests to detect Helicobacter pylori bacteria (bacteria in the stomach linked to ulcers), which can cause cancers [78] Medical Health Tests. Reasons, Procedure and Preparation for C Urea Breath Test-Carbon Urea Breath Test, Medical Health Tests (2014), Feb. 23; http://www.medicalhealthtests.com/urea-breath-test/c-urea-breath-test.html..
Carbon commonly has oxidation states from −4 to +4, with +4 in carbon dioxide (CO₂) and −4 in methane (CH₄). Its chemistry includes hydrocarbons, alcohols, acids, polymers, carbohydrates, proteins, and many other organic families. Important inorganic compounds include carbon monoxide (CO), carbonates such as calcium carbonate (CaCO₃), carbides such as silicon carbide (SiC), and cyanides such as sodium cyanide (NaCN). Graphene, fullerenes, and nanotubes are covalent carbon allotropes rather than compounds.
Carbon is found free in nature in three allotropic forms: graphite, diamond, and fullerines. A fourth form, known as "white" carbon, is now thought to exist. Ceraphite is one of the softest known materials while diamond is one of the hardest.
Graphite exists in two forms: alpha and beta. These have identical physical properties, except for their crystal structure. Naturally occurring graphites are reported to contain as much as 30% of the rhombohedral (beta) form, whereas synthetic materials contain only the alpha form. The hexagonal alpha type can be converted to the beta by mechanical treatment, and the beta form reverts to the alpha on heating it above 1000°C.
In 1969 a new allotropic form of carbon was produced during the sublimation of pyrolytic graphite at low pressures. Under free-vaporization conditions above ~2550°K, "white" carbon forms as small transparent crystals on the edges of the planes of graphite. The interplanar spacings of "white" carbon are identical to those of carbon form noted in the graphite gneiss from the Ries (meteroritic) Crater of Germany. "White" carbon is a transparent birefringent material. Little information is presently available about this allotrope.
In combination, carbon is found as carbon dioxide in the atmosphere of the earth and dissolved in all natural waters. It is a component of great rock masses in the form of carbonates of calcium (limestone), magnesium, and iron. Coal, petroleum, and natural gas are chiefly hydrocarbons.
Carbon is unique among the elements in the vast number and variety of compounds it can form. With hydrogen, oxygen, nitrogen, and other elements, it forms a very large number of compounds, carbon atom often being linked to another carbon atom. There are close to ten million known carbon compounds, many thousands of which are vital to organic and life processes.
Without carbon, the basis for life would be impossible. While it has been thought that silicon might take the place of carbon in forming a host of similar compounds, it is now not possible to form stable compounds with very long chains of silicon atoms. The atmosphere of Mars contains 96.2% CO2. Some of the most important compounds of carbon are carbon dioxide (CO2), carbon monoxide (CO), carbon disulfide (CS2), chloroform (CHCl3), carbon tetrachloride (CCl4), methane (CH4), ethylene (C2H4), acetylene (C2H2), benzene (C6H6), acetic acid (CH3COOH), and their derivatives.
See more information at the Carbon compound page.
Elemental diamond and graphite are chemically inert under ordinary handling, but fine carbon dust can irritate the lungs and may present a combustible dust hazard. Carbon monoxide (CO) is highly toxic because it binds hemoglobin strongly and impairs oxygen transport. Carbon dioxide (CO₂) is not very toxic chemically but can displace oxygen in confined spaces. Radioactive ¹⁴C is a low-energy beta emitter and is controlled as an internal exposure hazard.
Carbon cycles through the atmosphere, oceans, rocks, soils, and living organisms. Photosynthesis fixes carbon dioxide (CO₂) into biomass, while respiration, decay, combustion, and volcanism return carbon to air and water. Carbonate minerals are a major long-term sink, and dissolved inorganic carbon buffers seawater chemistry. Human release of fossil carbon has altered atmospheric CO₂ levels and the global carbon cycle.
Carbon is not a single commodity market because its forms have very different supply chains. Natural graphite is mined and beneficiated, while synthetic graphite is made from petroleum coke or other carbon-rich precursors at high temperature. Industrial diamond is produced mainly by high-pressure high-temperature synthesis or chemical vapor deposition, with natural diamond remaining important for gems. Carbon black is manufactured by controlled incomplete combustion or thermal decomposition of hydrocarbons. Activated carbon is made from coal, wood, coconut shell, or other carbonaceous feedstocks, and recycling is significant for some graphite and carbon-fiber applications but limited by quality requirements.
Made by burning organic compounds with insufficient oxygen.
Carbon is one of the more abundant elements in the universe and is made chiefly by helium fusion in stars through the triple-alpha process. It is found in interstellar molecules, dust grains, carbon-rich stars, meteorites, comets, planetary atmospheres, and organic material in small Solar System bodies. Its ability to form stable complex molecules makes it central to known planetary chemistry.
- Graphite conducts electricity well within its layers but much less well perpendicular to them.
- Diamond can burn in oxygen at high temperature to form carbon dioxide (CO₂).
- Natural diamond is metastable at Earth-surface conditions, but conversion to graphite is extremely slow.
- Carbon has two stable isotopes, ¹²C and ¹³C, and the cosmogenic radioisotope ¹⁴C is used in dating once-living materials
- Graphene is a single atomic layer of carbon arranged in a hexagonal lattice.
- Activated carbon works mainly by high internal surface area rather than by chemical neutralization.
Immagini
Proprietà
Fisiche
- Raggio atomico (empirico)
- 70 pm Confronta Raggio atomico (empirico) di tutti gli elementi →
- Raggio covalente
- 76 pm Confronta Raggio covalente di tutti gli elementi →
- Raggio di van der Waals
- 170 pm Confronta Raggio di van der Waals di tutti gli elementi →
- Densità
- 2267 kg/m³ Confronta Densità di tutti gli elementi →
- Volume molare
- 0,0053 L/mol
- Fase in condizioni STP
- Solido Confronta Fase in condizioni STP di tutti gli elementi →
- Punto di fusione
- 3549,85 °C Confronta Punto di fusione di tutti gli elementi →
- Punto di ebollizione
- 3824,85 °C Confronta Punto di ebollizione di tutti gli elementi →
- Conducibilità termica
- 1,59 W/(m·K) Confronta Conducibilità termica di tutti gli elementi →
- Capacità termica specifica
- 0,709 J/(g·K) Confronta Capacità termica specifica di tutti gli elementi →
- Capacità termica molare
- 8,517 J/(mol·K) Confronta Capacità termica molare di tutti gli elementi →
- Struttura cristallina
- Cubica tipo diamante Confronta Struttura cristallina di tutti gli elementi →
Chimiche
- Elettronegatività (Pauling)
- 2,55 Confronta Elettronegatività (Pauling) di tutti gli elementi →
- Elettronegatività (Allen)
- 2,544
- Affinità elettronica
- 1,2621 eV
- Energia di ionizzazione (1ª)
- 11,260288 eV Confronta Energia di ionizzazione (1ª) di tutti gli elementi →
- Energia di ionizzazione (2ª)
- 24,383227 eV Confronta Energia di ionizzazione (2ª) di tutti gli elementi →
- Energia di ionizzazione (3ª)
- 47,887945 eV Confronta Energia di ionizzazione (3ª) di tutti gli elementi →
- Energia di ionizzazione (4ª)
- 64,493742 eV Confronta Energia di ionizzazione (4ª) di tutti gli elementi →
- Energia di ionizzazione (5ª)
- 392,09191 eV Confronta Energia di ionizzazione (5ª) di tutti gli elementi →
- Stati di ossidazione
- −4, −3, −2, −1, 0, +1, +2, +3, +4 Confronta Stati di ossidazione di tutti gli elementi →
- Elettroni di valenza
- 4 Confronta Elettroni di valenza di tutti gli elementi →
- Allotropi
- ["graphite"]
- Configurazione elettronica
- [He] 2s2 2p2
Termodinamiche
- Punto triplo (temperatura)
- 4489 °C
- Punto triplo (pressione)
- 1,03e+7 Pa
- Calore di vaporizzazione
- 7,410478 eV Confronta Calore di vaporizzazione di tutti gli elementi →
- Calore di sublimazione
- 7,42789 eV
- Calore di atomizzazione
- 7,42789 eV
- Entalpia di atomizzazione
- 7,42986 eV
Nucleari
- Protoni
- 6 Confronta Protoni di tutti gli elementi →
- Neutroni
- 6 Confronta Neutroni di tutti gli elementi →
- Isotopi noti
- 16 Confronta Isotopi noti di tutti gli elementi →
- Isotopi stabili
- 2 Confronta Isotopi stabili di tutti gli elementi →
- Isotopo più stabile
- C-12
- Anno della scoperta
- 1797
Abbondanza
- Abbondanza (crosta terrestre)
- 200 mg/kg Confronta Abbondanza (crosta terrestre) di tutti gli elementi →
- Abbondanza (oceano)
- 28 mg/L Confronta Abbondanza (oceano) di tutti gli elementi →
Struttura cristallina
- Costante reticolare a
- 357 pm
Struttura elettronica
- Elettroni per guscio
- 2, 4 Confronta Elettroni per guscio di tutti gli elementi →
Identificativi
- Numero CAS
- 7440-44-0 Confronta Numero CAS di tutti gli elementi →
- Simbolo di termine
- 3P0
- InChI
- InChI=1S/C
- Chiave InChI
- OKTJSMMVPCPJKN-UHFFFAOYSA-N
Configurazione elettronica Misurato
C: 2s² 2p²[He] 2s² 2p²1s² 2s² 2p²Modello atomico
Gli isotopi modificano il numero di neutroni, la massa e la stabilità — non la configurazione elettronica di un atomo neutro.
Modello atomico schematico, non in scala.
Impronta atomica
Spettro di emissione / assorbimento
Distribuzione isotopica
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita |
|---|---|---|---|
| 12 Stabile | 12 | 98,9300% | Stabile |
| 13 Stabile | 13,00335483507 ± 0,00000000023 | 1,0700% | Stabile |
Fase / Stato
Motivo: 3799,8 °C sotto il punto di sublimazione (3824,85 °C)
Schema non in scala
Punti di transizione di fase
Energie di transizione
Energia necessaria per vaporizzare 1 mol al punto di ebollizione
Energia necessaria per sublimare 1 mol al punto di sublimazione
Densità
In condizioni standard
In condizioni standard
Avanzate
Spettri atomici
Sono visualizzati 10 di 11. Ordinamento per carica ionica crescente.
Righe disponibili ?
| Ione | Carica | Righe totali | Probabilità di transizione | Designazioni dei livelli |
|---|---|---|---|---|
| C I | 0 | 2102 | 1616 | 2102 |
| 12C I Isotopo | 0 | 89 | 0 | 89 |
| 13C I Isotopo | 0 | 89 | 0 | 89 |
| 12C II Isotopo | +1 | 187 | 0 | 187 |
| 14C II Isotopo | +1 | 187 | 0 | 187 |
| C II | +1 | 1605 | 1433 | 1605 |
| 13C II Isotopo | +1 | 187 | 0 | 187 |
| C III | +2 | 882 | 878 | 878 |
| C IV | +3 | 259 | 224 | 255 |
| C V | +4 | 149 | 146 | 147 |
Livelli disponibili ?
| Ione | Carica | Livelli |
|---|---|---|
| C I | 0 | 435 |
| 12C I Isotopo | 0 | 33 |
| 13C I Isotopo | 0 | 33 |
| 12C II Isotopo | +1 | 36 |
| 14C II Isotopo | +1 | 36 |
| C II | +1 | 415 |
| 13C II Isotopo | +1 | 36 |
| C III | +2 | 201 |
| C IV | +3 | 107 |
| C V | +4 | 156 |
Raggi ionici
| Carica | Coordinazione | Spin | Raggio |
|---|---|---|---|
| +4 | 4 | N/D | 15 pm |
| +4 | 6 | N/D | 16 pm |
Composti
Isotopi (2)
Carbon has seven isotopes. In 1961 the International Union of Pure and Applied Chemistry adopted the isotope carbon-12 as the basis for atomic weights. Carbon-14, an isotope with a half-life of 5715 years, has been widely used to date such materials as wood, archaeological specimens, etc.
| Numero di massa | Massa atomica (u) | Abbondanza naturale | Emivita | Modalità di decadimento | |
|---|---|---|---|---|---|
| 12 Stabile | 12 | 98,9300% ± 0,0800% | Stabile | stable | |
| 13 Stabile | 13,00335483507 ± 0,00000000023 | 1,0700% ± 0,0800% | Stabile | stable |
Righe spettrali
Sono visualizzati 50 di 993. Per impostazione predefinita sono mostrate soltanto le righe spettrali con intensità misurata.
| Lunghezza d'onda (nm) | Intensità | Stadio di ionizzazione | Tipo | Transizione | Accuratezza | Fonte | |
|---|---|---|---|---|---|---|---|
| 505.214927 nm | 160000 | C I | emission | 2s2.2p.3s 1P* → 2s2.2p.4p 1D | Misurata | NIST | |
| 538.033014 nm | 120000 | C I | emission | 2s2.2p.3s 1P* → 2s2.2p.4p 1P | Misurata | NIST | |
| 711.31656 nm | 110000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.4d 3F* | Misurata | NIST | |
| 493.202524 nm | 73000 | C I | emission | 2s2.2p.3s 1P* → 2s2.2p.4p 1S | Misurata | NIST | |
| 477.173374 nm | 69000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.4p 3P | Misurata | NIST | |
| 711.697758 nm | 45000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.5s 3P* | Misurata | NIST | |
| 658.76211 nm | 40000 | C I | emission | 2s2.2p.3p 1P → 2s2.2p.4d 1P* | Misurata | NIST | |
| 579.311495 nm | 38000 | C I | emission | 2s.2p3 3D* → 2s2.2p.4p 3P | Misurata | NIST | |
| 711.96559 nm | 37000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.5s 3P* | Misurata | NIST | |
| 580.059993 nm | 35000 | C I | emission | 2s.2p3 3D* → 2s2.2p.4p 3P | Misurata | NIST | |
| 600.1123 nm | 35000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.6s 3P* | Misurata | NIST | |
| 477.589266 nm | 34000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.4p 3P | Misurata | NIST | |
| 437.13814 nm | 33000 | C I | emission | 2s2.2p.3s 1P* → 2s2.2p.5p 1P | Misurata | NIST | |
| 711.145795 nm | 32000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.4d 3F* | Misurata | NIST | |
| 682.814076 nm | 27000 | C I | emission | 2s2.2p.3p 1P → 2s2.2p.4d 1D* | Misurata | NIST | |
| 504.149039 nm | 25000 | C I | emission | 2s.2p3 3D* → 2s2.2p.(2P*<1/2>).4f 2[5/2] | Misurata | NIST | |
| 477.002376 nm | 24000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.4p 3P | Misurata | NIST | |
| 600.6012 nm | 23000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.5d 3D* | Misurata | NIST | |
| 665.55294 nm | 20000 | C I | emission | 2s2.2p.3p 1P → 2s2.2p.5s 1P* | Misurata | NIST | |
| 710.011312 nm | 19000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.5s 3P* | Misurata | NIST | |
| 566.894 nm | 18000 | C I | emission | 2s2.2p.3p 1P → 2s2.2p.5d 1P* | Misurata | NIST | |
| 596.933151 nm | 18000 | C I | emission | 2s.2p3 3D* → 2s2.2p.4p 3D | Misurata | NIST | |
| 708.782188 nm | 18000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.4d 3D* | Misurata | NIST | |
| 402.94119 nm | 16000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.5p 3P | Misurata | NIST | |
| 601.64487 nm | 16000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.5d 3F* | Misurata | NIST | |
| 473.426281 nm | 15000 | C I | emission | 2s.2p3 3D* → 2s2.2p.5p 3P | Misurata | NIST | |
| 481.737213 nm | 15000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.4p 3S | Misurata | NIST | |
| 579.446608 nm | 15000 | C I | emission | 2s.2p3 3D* → 2s2.2p.4p 3P | Misurata | NIST | |
| 748.344451 nm | 15000 | C I | emission | 2s2.2p.3p 3S → 2s2.2p.4d 3P* | Misurata | NIST | |
| 406.52425 nm | 14000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.5p 3D | Misurata | NIST | |
| 580.52017 nm | 14000 | C I | emission | 2s.2p3 3D* → 2s2.2p.4p 3P | Misurata | NIST | |
| 601.4833 nm | 14000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.6s 3P* | Misurata | NIST | |
| 710.89263 nm | 14000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.5s 3P* | Misurata | NIST | |
| 400.9928 nm | 13000 | C I | emission | 2s2.2p.3s 1P* → 2s2.2p.6p 1P | Misurata | NIST | |
| 422.83269 nm | 13000 | C I | emission | 2s2.2p.3s 1P* → 2s2.2p.5p 1S | Misurata | NIST | |
| 447.85821 nm | 13000 | C I | emission | 2s.2p3 3D* → 2s2.2p.(2P*<1/2>).5f 2[5/2] | Misurata | NIST | |
| 504.012903 nm | 12000 | C I | emission | 2s.2p3 3D* → 2s2.2p.(2P*<1/2>).4f 2[7/2] | Misurata | NIST | |
| 601.0669 nm | 12000 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.6s 3P* | Misurata | NIST | |
| 406.4264 nm | 11000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.5p 3D | Misurata | NIST | |
| 639.7965 nm | 11000 | C I | emission | 2s2.2p.3p 3S → 2s2.2p.6s 3P* | Misurata | NIST | |
| 666.3043 nm | 11000 | C I | emission | 2s2.2p.3p 3P → 2s2.2p.5d 3D* | Misurata | NIST | |
| 667.1849 nm | 11000 | C I | emission | 2s2.2p.3p 3P → 2s2.2p.6s 3P* | Misurata | NIST | |
| 403.180216 nm | 10000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.5p 3P | Misurata | NIST | |
| 482.679468 nm | 10000 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.4p 3S | Misurata | NIST | |
| 598.903753 nm | 10000 | C I | emission | 2s.2p3 3D* → 2s2.2p.4p 3D | Misurata | NIST | |
| 707.649944 nm | 9900 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.4d 3D* | Misurata | NIST | |
| 402.284321 nm | 9700 | C I | emission | 2s2.2p.3s 3P* → 2s2.2p.5p 3P | Misurata | NIST | |
| 555.1578 nm | 9600 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.7s 3P* | Misurata | NIST | |
| 600.7173 nm | 9600 | C I | emission | 2s2.2p.3p 3D → 2s2.2p.6s 3P* | Misurata | NIST | |
| 502.492938 nm | 9400 | C I | emission | 2s.2p3 3D* → 2s2.2p.(2P*<3/2>).4f 2[7/2] | Misurata | NIST |
Proprietà estese
Raggi covalenti (dati estesi)
- Raggio covalente (Pyykkö)
- 75 pm
- Raggio covalente (Pyykkö, legame doppio)
- 67 pm
- Raggio covalente (Pyykkö, legame triplo)
- 60 pm
- Raggio covalente (Bragg)
- 77 pm
Raggi di van der Waals
- Bondi
- 170 pm
- Batsanov
- 170 pm
- Alvarez
- 177 pm
- UFF
- 385,1 pm
- MM3
- 204 pm
- Dreiding
- 389,83 pm
- Rowland–Taylor
- 177 pm
Raggi atomici e metallici
- Raggio atomico (Rahm)
- 190 pm
- Raggio metallico (C12)
- 86 pm
Scale di numerazione
- Mendeleev
- 87
- Pettifor
- 95
- Glawe
- 87
Scale di elettronegatività
- Ghosh
- 0
- Miedema
- 6
- Gunnarsson–Lundqvist
- 7
- Robles–Bartolotti
- 6
Polarizzabilità e dispersione
- Polarizzabilità dipolare
- 11,3 a.u.
- Polarizzabilità dipolare (inc.)
- 0,2 a.u.
- C₆
- 46,6 Ha·Bohr6
- C₆ (Gould–Bučko)
- 47,9 Ha·Bohr6
Parametri di Miedema
- Volume molare di Miedema
- 3,26 cm3/mol
- Densità elettronica di Miedema
- 6
Rischio di approvvigionamento ed economia
- Concentrazione della produzione
- 46
- Rischio relativo di approvvigionamento
- 5
- Distribuzione delle riserve
- 28
- Stabilità politica (principale produttore)
- 24
- Stabilità politica (principale detentore di riserve)
- 57
Transizioni di fase e allotropi
| Punto di ebollizione | 4098,15 K |
| Punto triplo (temperatura) | 4762,15 K |
| Punto triplo (pressione) | 10300 kPa |
Categorie degli stati di ossidazione
Dati di riferimento avanzati
Costanti di schermaggio (3)
| n | Orbitale | σ |
|---|---|---|
| 1 | s | 0,3273 |
| 2 | p | 2,8642 |
| 2 | s | 2,7834 |
Dettaglio dei raggi cristallini (3)
| Carica | CN | Spin | rcrystal (pm) | Origine |
|---|---|---|---|---|
| 4 | III | 6 | ||
| 4 | IV | 29 | Pauling's (1960) crystal radius, | |
| 4 | VI | 30 | Ahrens (1952) ionic radius, |
Modalità di decadimento degli isotopi (27)
| Isotopo | Modalità | Intensità |
|---|---|---|
| 8 | 2p | 100% |
| 9 | B+ | 100% |
| 9 | B+p | 7,5% |
| 9 | B+A | 38,4% |
| 10 | B+ | 100% |
| 11 | B+ | 100% |
| 14 | B- | 100% |
| 15 | B- | 100% |
| 16 | B- | 100% |
| 16 | B-n | 99% |
Fattori di diffusione dei raggi X (502)
| Energia (eV) | f₁ | f₂ |
|---|---|---|
| 10 | — | 0,80688 |
| 10,1617 | — | 0,85152 |
| 10,3261 | — | 0,89863 |
| 10,4931 | — | 0,94834 |
| 10,6628 | — | 1,0008 |
| 10,8353 | — | 1,05755 |
| 11,0106 | — | 1,12167 |
| 11,1886 | — | 1,18968 |
| 11,3696 | — | 1,26181 |
| 11,5535 | — | 1,33832 |
Dati aggiuntivi
Estimated Crustal Abundance
The estimated element abundance in the earth's crust.
2.00×102 milligrams per kilogram
Riferimenti (1)
Estimated Oceanic Abundance
The estimated element abundance in the earth's oceans.
2.8×101 milligrams per liter
Riferimenti (1)
Isotopes in Forensic Science and Anthropology
Information on the use of this element's isotopes in forensic science and anthropology.
Variations in the isotope-amount ratio n(13C)/n(12C) of biological products can be observed using isotope-ratio mass spectrometry (IRMS) to detect adulteration (the addition of inferior ingredients) in honey and other food products.
The isotope-amount ratio n(13C)/n(12C) can fluctuate between carbon sources, for example C3 plants (found in temperate climates and which use atmospheric carbon dioxide to make a 3-carbon molecule during photosynthesis — examples include rice, potatoes, tomatoes, and sugar beets), C4 plants (found in hot climates and which use atmospheric carbon dioxide to make a 4-carbon molecule during photosynthesis — examples include corn and sugar cane), animal carbon, atmospheric CO2, etc. This commonly makes it possible to detect whether these different carbon sources have been mixed by using isotope or mass balance to distinguish, for example, between beet sugar and cane sugar. Complications in source identification can arise with plants that open stomata at night to collect carbon dioxide to use a third mechanism to fix atmospheric carbon dioxide (CAM or crassulacean acid metabolism). The isotope-amount ratio n(13C)/n(12C) of CAM plants overlaps that of C3 or C4 plants — examples include pineapples and jade plants. The following adulterations are commonly detected using stable carbon isotope IRMS:
–Variations in the isotope-amount ratio n(13C)/n(12C) of honey are used to detect the addition (and potential adulteration) of high fructose corn syrup, corn, or sugar cane [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)..
–Variations in the isotope-amount ratio n(13C)/n(12C) of fruit juice have been used to detect the addition of a sugar [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)..
–Variations in the isotope-amount ratio n(13C)/n(12C) of natural vanilla extract have been used to detect the addition of artificial vanillin or p-hydroxybenzaldehyde [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)..
–Variations in the isotope-amount ratio n(13C)/n(12C) of beer are used to detect C4 carbon, which would indicate that a beer company may have added ingredients that are not traditionally used in brewing beer. Therefore, this ratio is used to detect the misrepresentation of a product as being pure [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)., [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002)..
Stable carbon IRMS has been used to determine if the botanical origin of an alcoholic spirit has been mislabeled and if chaptalization (the process of adding sugar to increase the alcoholic content) of wine has occurred [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)., [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002).. 14C scintillation counting has been used to determine the age of wine and alcoholic spirits [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002)., [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002).. Variations in the isotope-amount ratio n(13C)/n(12C) of urine has been used to determine if steroids in urine are natural or of synthetic origin. These measurements enable anti-doping laboratories to perfect their methods for detecting steroid doping in athletes [69] B. D. Ahrens, A. W. Butch. Drug Test Anal.5, 534 (2013)., [70] E. Bulska, D. Gorczyca, I. Zalewska, A. Pokrywka, D. Kwiatkowska. J. Pharm. Biomed. Anal.106, 159 (2015)., [71] A. Casilli, T. Piper, F. A. de Oliveira, M. Costa Padilha, H. Marcelo Pereira, M. Thevis, F. R. de Aquino Neto. Drug Test Anal.8, 1204 (2016).. Variations in the isotope-amount ratio n(13C)/n(12C) of marijuana can provide information to determine if the plants were grown “inside” a building or greenhouse or were “open grown” (Fig. IUPAC.6.4). Plant carbon isotopic compositions are controlled by atmospheric CO2 and the supply and demand of CO2 in photosynthesis (the process used by plants to convert light energy from the sun into chemical energy). “Open grown” plants are grown in an area that is well ventilated and receives natural CO2. In contrast, plants grown “inside” receive supplemented CO2 and the photosynthesis process is more confined. Additionally, CO2 from a tank of compressed gas used to augment atmospheric CO2 to increase the growth of marijuana plants is commonly highly depleted in 13C as a refinery by-product. These differences change the carbon isotope ratios of the plants and the ratios vary enough to enable the determination of the growing and cultivation process of marijuana [72] E. K. Shibuya, J. E. Souza Sarkis, O. N. Neto, M. Z. Moreira, R. L. Victoria. Forensic Sci. Int.160, 35 (2006)., [73] J. B. West, J. M. Hurley, J. R. Ehleringer. J Forensic Sci.54, 84 (2009)..
Riferimenti (9)
- [67] C. Cordella, I. Moussa, A. C. Martel, N. Sbirrazzuoli, L. Lizzani-Cuvelier. J. Agric. Food. Chem.50, 1751 (2002).
- [68] J. R. Brooks, N. Buchmann, S. Phillips, B. Ehleringer, R. D. Evans, M. Lott, L. A. Martinelli, W. T. Pockman, D. Sandquist, J. P. Sparks, L. Sperry, D. Williams, J. R. Ehleringer. J. Agric. Food. Chem.50, 6413 (2002).
- [69] B. D. Ahrens, A. W. Butch. Drug Test Anal.5, 534 (2013).
- [70] E. Bulska, D. Gorczyca, I. Zalewska, A. Pokrywka, D. Kwiatkowska. J. Pharm. Biomed. Anal.106, 159 (2015).
- [71] A. Casilli, T. Piper, F. A. de Oliveira, M. Costa Padilha, H. Marcelo Pereira, M. Thevis, F. R. de Aquino Neto. Drug Test Anal.8, 1204 (2016).
- [72] E. K. Shibuya, J. E. Souza Sarkis, O. N. Neto, M. Z. Moreira, R. L. Victoria. Forensic Sci. Int.160, 35 (2006).
- [73] J. B. West, J. M. Hurley, J. R. Ehleringer. J Forensic Sci.54, 84 (2009).
- [74] United States Drug Enforcement Administration. Marijuana-Indoor Marijuana Grow, United States Department of Justice (2014), Feb. 22; http://www.justice.gov/dea/pr/multimedia-library/image-gallery/images_marijuana.shtml.
- [4] IUPAC Periodic Table of the Elements and Isotopes (IPTEI) https://doi.org/10.1515/pac-2015-0703
Riferimenti
(9)
Data deposited in or computed by PubChem
The half-life and atomic mass data was provided by the Atomic Mass Data Center at the International Atomic Energy Agency.
Element data are cited from the Atomic weights of the elements (an IUPAC Technical Report). The IUPAC periodic table of elements can be found at https://iupac.org/what-we-do/periodic-table-of-elements/. Additional information can be found within IUPAC publication doi:10.1515/pac-2015-0703 Copyright © 2020 International Union of Pure and Applied Chemistry.
The information are cited from Pure Appl. Chem. 2018; 90(12): 1833-2092, https://doi.org/10.1515/pac-2015-0703.
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is one of 17 national laboratories funded by the U.S. Department of Energy. The lab's primary mission is to conduct basic research of the atom's nucleus using the lab's unique particle accelerator, known as the Continuous Electron Beam Accelerator Facility (CEBAF). For more information visit https://www.jlab.org/
The periodic table at the LANL (Los Alamos National Laboratory) contains basic element information together with the history, source, properties, use, handling and more. The provenance data may be found from the link under the source name.
The periodic table contains NIST's critically-evaluated data on atomic properties of the elements. The provenance data that include data for atomic spectroscopy, X-ray and gamma ray, radiation dosimetry, nuclear physics, and condensed matter physics may be found from the link under the source name. Ref: https://www.nist.gov/pml/atomic-spectra-database
This section provides all form of data related to element Carbon.
The element property data was retrieved from publications.