Carbon

Symbol: C
Atomic number: 6
Category: nonmetals
Group: 14
Period: 2
Block: p
Atomic weight: 12.0107 g/mol
Electrons per shell: 2, 4
CAS number: 7440-44-0
Phase: solid
Density: 1.8 - 2.1 kg/dm³ (amorphous) - near r.t. 2.267 kg/dm³ (graphite) - near r.t 3.515 kg/dm³ (diamond) - near r.t.
Melting point: 3800 (graphite) K (3527 °C, 6381 °F)
Boiling point: 4300 K (4027 °C, 7281 °F)
Crystal structure: graphite: hexagonal diamond: isometric-hexoctahedral
Oxidation states: -4, -3, -2, -1, 0, 1, 2, 3, 4
Electronegativity: 2.55 (Pauling scale)
Name's origin: carbo
Name's meaning: a Latin word meaning charcoal as carbon is found in it
Facts:
- has lots of allotropic forms - e.g. diamond, amorphous carbon, graphite and fullerene
- is the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen
- is present in all known lifeforms, and in the human body carbon is the second most abundant element by mass (about 18.5 %) after oxygen
- is the chemical basis of all known life
- all the allotropic forms are solids under normal conditions
- pure carbon has extremely low toxicity and can be handled and even ingested safely in the form of graphite or charcoal graphite is the most thermodynamically stable
- diamond is among the hardest materials known, while graphite is soft enough to form a streak on paper
- diamond has the highest thermal conductivity of all known materials