Carbon (C)
Element 6 · Nonmetal · atomic mass 12.011 u · group 14, period 2
Electron shells: 2, 4
Carbon forms more compounds than every other element combined, because it bonds readily to itself in chains and rings. All known life is built on that chemistry.
Diamond and pencil graphite are the same element — only the bonding arrangement differs.
- Atomic number
- 6
- Atomic mass
- 12.011 u
- Electron configuration
- [He] 2s² 2p²
- Group · period · block
- 14 · 2 · p
- Oxidation states
- −4, +2, +4
- Electronegativity
- 2.55 (Pauling)
- Melting point
- 3,550 °C
- Boiling point
- 3,825 °C
- Density
- 2.267 g/cm³
- State at 20 °C
- Solid
- Appearance
- Black (graphite) or transparent (diamond)
- Discovered
- Known since antiquity
6 protons, and 6 electrons when neutral
IUPAC interval [12.0096, 12.0116]
Carbon group
What Carbon is used for
- Steelmaking
- Carbon-fibre composites
- Activated carbon filtration
- Graphite electrodes and pencil leads
Atomic structure of Carbon
A neutral carbon atom has 6 protons and 6 electrons. Its most common isotope carries about 6 neutrons, which is where the mass number 12 comes from. Change the neutron count and you have a different isotope of carbon; change the proton count and you have a different element entirely.
Those electrons fill shells from the inside out: 2, 4. In orbital notation that is [He] 2s² 2p², leaving 4 valence electrons in the outer shell — the ones that do the chemistry.
3D electron orbitals
See where Carbon's electrons actually are — a cloud of 26,000 points sampled from the probability density |ψ|², not a cartoon of a lobe.
Where Carbon sits in the periodic table
Discovery and naming
Carbon has been known and used since antiquity, long before anyone could describe it as an element. Its name comes from Latin carbo, "coal".
Keep exploring
Atomic weight from IUPAC/CIAAW; physical properties from PubChem (US National Library of Medicine). Values that have never been measured are shown as “not measured” rather than estimated.
Related Calculators
Frequently Asked Questions
What is the atomic mass of Carbon?
The standard atomic weight of Carbon is 12.011 u. Because the natural isotope mix varies between sources, IUPAC publishes it as the interval [12.0096, 12.0116], and 12.011 is the conventional single value to use in calculations.
How many protons, neutrons and electrons does Carbon have?
Carbon has 6 protons, because the atomic number is the proton count and that is what makes an atom Carbon at all. A neutral Carbon atom has the same number of electrons, 6. The neutron count varies by isotope; the most common one has about 6, since 12 − 6 = 6.
What is the electron configuration of Carbon?
The electron configuration of Carbon is [He] 2s² 2p². Its electrons are arranged 2, 4 across 2 shells.
Is Carbon a metal?
No. Carbon is classified as a nonmetal, on the right-hand side of the table where elements gain or share electrons rather than losing them.
What group and period is Carbon in?
Carbon is in group 14 (the carbon group), period 2, in the p-block. The group is its column and the period is its row.
What is the charge of Carbon?
Carbon most commonly forms a 4+ or 4− ion. It has 4 outer electrons available to lose. Across all its compounds it shows oxidation states of −4, +2, +4.
What is the melting point of Carbon?
Carbon melts at 3,550 °C and boils at 3,825 °C. That puts it in the solids at everyday temperatures.
What is Carbon used for?
Steelmaking, Carbon-fibre composites, Activated carbon filtration, Graphite electrodes and pencil leads. Carbon forms more compounds than every other element combined, because it bonds readily to itself in chains and rings.
Who discovered Carbon, and where does its name come from?
Carbon (C) has been known and used since antiquity, long before anyone could describe it as an element. The name comes from Latin carbo, "coal".