ElementsWhat is carbon?
Carbon is the base of all known life. Pure carbon takes very different forms: soft black graphite, hard clear diamond, and thin sheets called graphene. Coal, oil, limestone and the carbon dioxide in air all contain it.
What is carbon used for?
Steel making, fuels, plastics, pencil leads, water filters, carbon fibre for light strong parts, and diamond cutting tools.
Where the name comes from
From the Latin word carbo, meaning coal or charcoal.
Key facts
- Symbol
- C
- Atomic number
- 6
- Atomic mass
- 12.011 u
- Family
- Nonmetal
- Period
- 2
- Group
- 14
- Block
- p
- State at room temperature
- Solid
- Melting point
- 3,550 °C (3,823 K, 6,422 °F)
- Boiling point
- 3,825 °C (4,098 K, 6,917 °F)
- Density
- 2.27 g/cm³
- Electrons per shell
- 2, 4
- Electron configuration
- [He]2s2 2p2
- Common oxidation states
- +4, +2, -4
- Electronegativity (Pauling)
- 2.55
- First ionisation energy
- 11.26 eV
- Electron affinity
- 1.263 eV
- Atomic radius (van der Waals)
- 170 pm
- Discovered
- Known since ancient times
Place in the periodic table
Carbon is element number 6. It sits in period 2 (row 2) of the periodic table, in group 14 (column 14), and belongs to the p-block. Just before it comes boron (5), and just after it comes nitrogen (7). In the same column, silicon is below it. Elements in one column tend to behave alike.
Family: Nonmetals.
Physical properties
At room temperature carbon is a solid. Reference tables list a melting point of 3,550 °C and a boiling point of 3,825 °C, but at normal pressure carbon does not melt: it turns straight from solid to vapour. Its density is 2.27 grams per cubic centimetre, so a one-litre block would weigh about 2.27 kilograms. By density it ranks 75th among the 96 elements with a measured value. It has the highest melting point of all elements.
Inside the atom
An atom of carbon has 6 protons in its nucleus and, when neutral, 6 electrons around it. The electrons are arranged in 2 shells: 2, 4. The outermost shell holds 4 electrons. Written in full, the electron configuration is [He]2s2 2p2.
Its electronegativity on the Pauling scale is 2.55. This number shows how strongly an atom pulls shared electrons towards itself: fluorine, the strongest, is 3.98. Removing one electron from an atom takes 11.26 electronvolts (about 1,086 kilojoules per mole). One mole of carbon weighs 12.011 grams, so a single gram contains about 5.01 × 1022 atoms.
The ring picture is a simple model that only counts the electrons in each shell. Real atoms do not look like this.
Next steps
- Work out the weight of a compound that contains carbon with the molar mass calculator.
- Compare it with every other element in the sortable list.
- Test yourself with the symbol quiz.
Figures on this page are from PubChem (U.S. National Library of Medicine), as downloaded on 11 November 2026. See About and data sources.