Carbon
Carbon occurs naturally in two allotropic forms, namely graphite and diamond; the discovery in 1985 of fullerenes has increased the number of allotropic forms of this element. The study of carbon and its organic compounds is the basis of organic chemistry. The applications for carbon are many and include its use as an alloying element with iron in the manufacture of steel, its use as brushes in electrical generators and motors, the use of colloidal graphite or carbon to coat surfaces, in electrical assemblies to absorb microwaves and inhibit photoelectrons and secondary electrons, and the use of high purity carbon (graphite) in nuclear reactors to moderate neutrons. Diamond has unique properties, being one of the hardest materials known and with excellent corrosion resistance and thermal transfer. Industrial diamond is used in rock drilling equipment and abrasive materials.
- Symbol
- C
- Discovered
- Known since prehistoric times.
- Abundance
- 480 ppm of the Earth’s crust. The human body contains approximately 16kg of carbon in one form or another.
Atomic number | 6 | Clip | |
Mass number | 12 | Clip | |
Atomic / Molecular Weight | 12.011 | gmol-1 | Clip |
Density | 2266 | kgm-3 | Clip |
Lattice constant | 357 | fm | Clip |
Linear expansivity | 1e-6 to 3.1e-6 | K-1 | Clip |
Specific heat capacity | 711 graphite, 519 diamond | Jkg-1K-1 | Clip |
Refractive index | 2.417 diamond | at 589.3nm 101.3kPa 0°C | Clip |
Bulk Modulus of Rigidity | 542e9 (diamond) 33e9 (graphite) | Nm-2 | Clip |

See also: Asymmetric Carbon Atom, Carbanion, Carbocation, Carbon Cycle, Carbon Deposit, Carbon Disulphide, Carbon Monoxide, Carbon Nanotubes, Carbon Tetrachloride, Carbonado, Diamond, Hydrocarbon, Organic Chemistry, Organic Compound, Periodic Table.
Subjects: Chemistry