Carbon
General:
Name: Carbon
Type: Non-Metal, Carbon group
Density @ 293 K: 2.267 g/cm3 (graphite), 3.513 g/cm3 (diamond)
Type: Non-Metal, Carbon group
Density @ 293 K: 2.267 g/cm3 (graphite), 3.513 g/cm3 (diamond)
Symbol: C
Atomic weight: 12.011
Atomic volume: 5.31 cm3/mol (graphite), 3.42 cm3/mol (diamond)
Atomic weight: 12.011
Atomic volume: 5.31 cm3/mol (graphite), 3.42 cm3/mol (diamond)
States
State (s, l, g): solid
Melting point: 3823 K (3550 oC)
Melting point: 3823 K (3550 oC)
Boiling point: 4300 K (4027 oC)
Note: At normal pressures, carbon does not melt when heated, it sublimes - i.e. when heated, carbon undergoes a phase change directly from solid to gas, much like dry ice (solid carbon dioxide) does. The melting point quoted above is under a pressure of 10 atmospheres.
Appearance
Structure: hexagonal layers (graphite), tetrahedral (diamond)
Hardness: 0.5 mohs (graphite), 10.0 mohs (diamond)
Hardness: 0.5 mohs (graphite), 10.0 mohs (diamond)
Color: black (graphite), transparent (diamond)
Harmful effects:
Pure carbon has very low toxicity. Inhalation of large quantities of carbon black dust (soot/coal dust) can cause irritation and damage to the lungs.
Reactions & Compounds
Reaction with air: vigorous, ⇒ CO2
Reaction with 15 M HNO3: mild, w/ht ⇒ C6(CO2H)6 (mellitic/graphitic acid)
Oxide(s): CO , CO2
Hydride(s): CH4 and many CxHy
Reaction with 15 M HNO3: mild, w/ht ⇒ C6(CO2H)6 (mellitic/graphitic acid)
Oxide(s): CO , CO2
Hydride(s): CH4 and many CxHy
Reaction with 6 M HCl: none
Reaction with 6 M NaOH: none
Chloride(s): CCl4
Reaction with 6 M NaOH: none
Chloride(s): CCl4
Radius
Atomic radius: 70 pm
Ionic radius (2+ ion): pm
Ionic radius (2- ion): pm
Ionic radius (2+ ion): pm
Ionic radius (2- ion): pm
Ionic radius (1+ ion): pm
Ionic radius (3+ ion): pm
Ionic radius (1- ion): pm
Ionic radius (3+ ion): pm
Ionic radius (1- ion): pm
Conductivity
Thermal conductivity: 25-470 W m-1 K-1 (graphite)
470 W m-1 K-1 (diamond)
470 W m-1 K-1 (diamond)
Electrical conductivity: 0.07 x 106 S cm-1
Features:
Carbon can exist with several different 3-dimensional structures in which atoms are arranged differently (allotropes).
Three common crystalline allotropes are graphite, diamond, and (usually) fullerines. (Fullerines may sometimes exist in amorphous form.) (9)
Carbon can also exist in an amorphous state. Many commonly described as amorphous allotropes, however, as glassy carbon, soot or carbon black are usually enough structure to not be truly amorphous. Although crystalline nanotubes were observed, they are generally amorphous (10).
The structures of eight allotropes are displayed at the bottom of this page.
Interestingly, the graphite is one of the sweetest substances and diamonds was thought until recently to be the hardest substance of natural origin.
An extremely rare allotrope of carbon, lonsdaleite was calculated, in its pure form, 58% stronger than diamond. Lonsdaleite is a network of diamond-like carbon with a hexagonal structure of graphite. It is made when meteorites containing graphite hit another body, like the Earth. The high temperatures and pressures transform the impact of graphite lonsdaleite.
Carbon is the highest melting / sublimation point of all elements and, in the form of diamond has the highest thermal conductivity of any element.
Diamond high thermal conductivity is the origin of the slang expression "ice". A typical room temperature of your body temperature is higher than the room - including large diamonds, you can just happen to have lying around in the room. If you touch any of these diamonds, their high thermal conductivity carries heat away from your skin faster than any other material. Your brain interprets this rapid transfer of heat energy from your skin to mean that you touch something very cold - for diamond at room temperature can feel like ice.
Uses:
Carbon (as coal, which is essentially carbon) is used as fuel.
Graphite is used pencil stubs, crucibles at high temperatures, dry cells, electrodes and as a lubricant.
The diamonds used in jewelry and - because they are so difficult - in the industry for cutting, drilling, grinding and polishing.
Carbon black is used as black pigment in printing ink.
Carbon can form alloys with iron, the most common is carbon steel.
The radioactive isotope 14C is used in archaeological dating.
Carbon compounds are important in many areas of the chemical industry - carbon forms many compounds with elements hydrogen, oxygen, nitrogen and others.
Its ability to form long-chain complex compounds of carbon led to acting as the basis for all life on Earth.
The exceptional physical properties of carbon allotropes such as nanotubes news - such as high thermal conductivity and resistance - offers enormous potential for future development.
Carbon can exist with several different 3-dimensional structures in which atoms are arranged differently (allotropes).
Three common crystalline allotropes are graphite, diamond, and (usually) fullerines. (Fullerines may sometimes exist in amorphous form.) (9)
Carbon can also exist in an amorphous state. Many commonly described as amorphous allotropes, however, as glassy carbon, soot or carbon black are usually enough structure to not be truly amorphous. Although crystalline nanotubes were observed, they are generally amorphous (10).
The structures of eight allotropes are displayed at the bottom of this page.
Interestingly, the graphite is one of the sweetest substances and diamonds was thought until recently to be the hardest substance of natural origin.
An extremely rare allotrope of carbon, lonsdaleite was calculated, in its pure form, 58% stronger than diamond. Lonsdaleite is a network of diamond-like carbon with a hexagonal structure of graphite. It is made when meteorites containing graphite hit another body, like the Earth. The high temperatures and pressures transform the impact of graphite lonsdaleite.
Carbon is the highest melting / sublimation point of all elements and, in the form of diamond has the highest thermal conductivity of any element.
Diamond high thermal conductivity is the origin of the slang expression "ice". A typical room temperature of your body temperature is higher than the room - including large diamonds, you can just happen to have lying around in the room. If you touch any of these diamonds, their high thermal conductivity carries heat away from your skin faster than any other material. Your brain interprets this rapid transfer of heat energy from your skin to mean that you touch something very cold - for diamond at room temperature can feel like ice.
Uses:
Carbon (as coal, which is essentially carbon) is used as fuel.
Graphite is used pencil stubs, crucibles at high temperatures, dry cells, electrodes and as a lubricant.
The diamonds used in jewelry and - because they are so difficult - in the industry for cutting, drilling, grinding and polishing.
Carbon black is used as black pigment in printing ink.
Carbon can form alloys with iron, the most common is carbon steel.
The radioactive isotope 14C is used in archaeological dating.
Carbon compounds are important in many areas of the chemical industry - carbon forms many compounds with elements hydrogen, oxygen, nitrogen and others.
Its ability to form long-chain complex compounds of carbon led to acting as the basis for all life on Earth.
The exceptional physical properties of carbon allotropes such as nanotubes news - such as high thermal conductivity and resistance - offers enormous potential for future development.
Energies
Specific heat capacity: 0.71 J g-1 K-1 (graphite), 0.5091 J g-1 K-1 (diamond)
Heat of fusion: 117 kJ mol-1 (graphite)
1st ionization energy: 1086.5 kJ mol-1
3rd ionization energy: 4620.5 kJ mol-1
Heat of fusion: 117 kJ mol-1 (graphite)
1st ionization energy: 1086.5 kJ mol-1
3rd ionization energy: 4620.5 kJ mol-1
Heat of atomization: 717 kJ mol-1
Heat of vaporization: 710.9 kJ mol-1
2nd ionization energy: 2352.6 kJ mol-1
Electron affinity: 121.55 kJ mol-1
Heat of vaporization: 710.9 kJ mol-1
2nd ionization energy: 2352.6 kJ mol-1
Electron affinity: 121.55 kJ mol-1
Oxidation & Electrons
Shells: 2,4
Minimum oxidation number: -4
Min. common oxidation no.: -4
Electronegativity (Pauling Scale): 2.55
Minimum oxidation number: -4
Min. common oxidation no.: -4
Electronegativity (Pauling Scale): 2.55
Electron configuration: 1s2 2s2 2p2
Maximum oxidation number: 4
Max. common oxidation no.: 4
Polarizability volume: 1.8 Å3
Maximum oxidation number: 4
Max. common oxidation no.: 4
Polarizability volume: 1.8 Å3
Abundance & Isotopes
Abundance earth's crust: 200 parts per million by weight, 344 parts per million by moles
Abundance solar system: 3000 parts per million by weight, 300 parts per million by moles
Cost, pure: $2.4 per 100g
Cost, bulk: $ per 100g
Source: Carbon can be obtained by burning organic compounds with insufficient oxygen. The four main allotropes of carbon are graphite, diamond, amorphous carbon and fullerines. Natural diamonds are found in kimberlite from ancient volcanoes. Graphite can also be found in natural deposits. Fullerenes were discovered as byproducts of molecular beam experiments in the 1980s. Amorphous carbon is the main constituent of charcoal, soot (carbon black), and activated carbon.
Isotopes: 13 whose half-lives are known, with mass numbers 8 to 20. Of these, two are stable, 12C and 13C. Isotope 14C, with a half-life of 5730 years, is widely used to date carbonaceous materials such as wood, archeological specimens, etc for ages up to about 40 000 years.
Abundance solar system: 3000 parts per million by weight, 300 parts per million by moles
Cost, pure: $2.4 per 100g
Cost, bulk: $ per 100g
Source: Carbon can be obtained by burning organic compounds with insufficient oxygen. The four main allotropes of carbon are graphite, diamond, amorphous carbon and fullerines. Natural diamonds are found in kimberlite from ancient volcanoes. Graphite can also be found in natural deposits. Fullerenes were discovered as byproducts of molecular beam experiments in the 1980s. Amorphous carbon is the main constituent of charcoal, soot (carbon black), and activated carbon.
Isotopes: 13 whose half-lives are known, with mass numbers 8 to 20. Of these, two are stable, 12C and 13C. Isotope 14C, with a half-life of 5730 years, is widely used to date carbonaceous materials such as wood, archeological specimens, etc for ages up to about 40 000 years.
Discovery of carbon:
"Carbon" is derived from the Latin "carbo" meaning coal.
Carbon has been known since antiquity as soot, charcoal, graphite and diamond. Ancient cultures did not realize, of course, that these substances were different forms of the same element.
Antoine Lavoisier called carbon and conducted some of the early experiments to reveal its nature. In 1694, he shared their resources with other chemists to buy a diamond, they are placed in a glass jar closed. They focused the sun's rays on the diamond with a loupe remarkable - illustration to the right - and I saw the diamond burn and disappear. Lavoisier noted the weight of the pot has remained unchanged and that when it burned, the diamond was combined with oxygen to form carbon dioxide. He concluded that the diamond and coal have been made of the same element - carbon.
In 1779, Carl Scheele showed that graphite burned to form carbon dioxide and should be another form of carbon
In 1796 Smithson Tennant was determined that pure carbon diamond and not a compound of carbon, it burns to form carbon dioxide only. Tennant has also shown that when equal weight of coal and diamonds were burned, they produced the same amount of carbon dioxide.
"Carbon" is derived from the Latin "carbo" meaning coal.
Carbon has been known since antiquity as soot, charcoal, graphite and diamond. Ancient cultures did not realize, of course, that these substances were different forms of the same element.
Antoine Lavoisier called carbon and conducted some of the early experiments to reveal its nature. In 1694, he shared their resources with other chemists to buy a diamond, they are placed in a glass jar closed. They focused the sun's rays on the diamond with a loupe remarkable - illustration to the right - and I saw the diamond burn and disappear. Lavoisier noted the weight of the pot has remained unchanged and that when it burned, the diamond was combined with oxygen to form carbon dioxide. He concluded that the diamond and coal have been made of the same element - carbon.
In 1779, Carl Scheele showed that graphite burned to form carbon dioxide and should be another form of carbon
In 1796 Smithson Tennant was determined that pure carbon diamond and not a compound of carbon, it burns to form carbon dioxide only. Tennant has also shown that when equal weight of coal and diamonds were burned, they produced the same amount of carbon dioxide.
In 1855, Benjamin Brodie pure graphite carbon products, graphite was proving a form of carbon
Although it was already tried, unsuccessfully, in 1955, Francis Bundy and his colleagues at General Electric has finally shown that the graphite can be transformed into diamond at high temperature and high pressure.
In 1985, Robert Curl, Harry Kroto and Richard Smalley discovered fullerenes, a new form of carbon in which atoms are arranged in shapes of footballs.
The most recently discovered allotrope of carbon is graphene, which consists of a single layer of graphite. Graphene has a thickness of only one atom. Its discovery was announced in 2004 by Kostya Novoselov and Andre Geim, who used duct tape to detach a single layer of graphite atoms to produce the new allotrope.
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