Carbon Facts – Atomic Number 6 – Element Symbol C 2

Carbon Facts - Element
Carbon is atomic number 6 on the periodic table with element symbol C.

Carbon is the sixth element of the periodic table. These carbon facts contain chemical and physical data along with general information and history.

Fun Carbon Facts

  • The carbon allotrope named graphite is one of the softest materials where diamonds are one of the hardest.
  • Graphite is shiny and black, diamonds are colorless transparent solids and fullerenes and amorphous carbon are both black, soot-like powders.
  • Carbon atoms can form chains and rings and sealed with hydrogen atoms to form compounds called hydrocarbons. These compounds are the basis of organic chemistry.
  • Carbon is a nonmetal that can form over 10 million different compounds.
  • Carbon has the highest sublimation point of all the elements. Diamonds melt around 3550 ºC and other allotropes sublime at around 3800 ºC.
  • Pure carbon is one of the few elements that exists free in nature.
  • Carbon is the fourth most abundant element in the universe by mass.
  • 18% of your body weight is carbon.
  • Graphite is used as a thermal insulator. It is also a good conductor of electricity.
  • Carbon-14 is used to date once living matter in a process known as Carbon Dating.

Basic Carbon Facts

Here are the essential facts for the element carbon:

Name: Carbon

Atomic Number: 6

Element Symbol: C

Group: 14

Period: 2

Block: p

Element Family: nonmetal

Atomic Mass: [12.0096; 12.0116] IUPAC guidelines. For single value, use 12.011.

Electron Configuration: [He]2s22p(shorthand) or 1s22s22p(full)

Discovery: Carbon has been known about since prehistoric times.

Name Origin: The name carbon comes from the Latin word carbo, meaning charcoal.

Common Allotropes: Carbon has numerous allotropes, including amorphous carbon, diamond, fullerene, graphene, graphite, and nanotubules.

Natural Isotopes:

Natural boron is comprised of two stable isotopes and one radioactive isotope.

Carbon-12 is a stable isotope containing 6 neutrons. Approximately 99% of all natural carbon is carbon-12.

Carbon-13 is a stable isotope containing 7 neutrons. Most of the rest of natural carbon is carbon-13.

Carbon-13 is a radioactive isotope containing 8 neutrons. Carbon-14 occurs naturally in trace amounts. It decays by β- decay into 14N with a half-life of 5730 years.

There are 12 known artificial radioisotopes ranging from carbon-8 to carbon-22.

Physical Data

Carbon Graphite (USGS)
Carbon Graphite (USGS)

Graphite: 2.2 g/cm3
Diamond: 3.513 g/cm3

Sublimation Point: 3915 K ​(3642 °C, ​6588 °F)

Triple Point: 4600 K at ​10800 kPa

State at 20ºC: Solid

Heat of Fusion: Graphite: 117 kJ/mol

Molar Heat Capacity:
Graphite: 8.517 J/mol·K
Diamond: 6.155 J/mol·K

Atomic Data

Carbon Atom
Electron configuration of a carbon atom.

Atomic Radius: 1.70 Å

Covalent Radius: sp3: 0.77 Å
sp2: 0.73 Å
sp: 0.69 Å

Van der Waals Radius:  1.70 Å

Electron Affinity: 121.776 kJ/mol

Electronegativity: (Pauling scale): 2.55

1st Ionization Energy: 1086.454 kJ/mol

2nd Ionization Energy: 2352.631 kJ/mol

3rd Ionization Energy: 4620.471 kJ/mol

4th Ionization Energy: 6222.716 kJ/mol

5th Ionization Energy: 37830.648 kJ/mol

6th Ionization Energy: 47277.174 kJ/mol

Common Oxidation States: +4, -4 (common), +3, +2, +1, 0, -1, -2, -3 (uncommon)

Learn more about elements on the periodic table.


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