Carbon
nonmetalProperties
| Property | Value |
|---|---|
| Atomic Mass | 12.011 amu |
| Category | nonmetal |
| Group | 14 |
| Period | 2 |
| Electron Configuration | 1s2 2s2 2p2 |
| Electronegativity | 2.55 (Pauling) |
| Oxidation States | 4, 2, -4 |
| Melting Point | 3823 K (3549.8 °C) |
| Boiling Point | 4098 K (3824.8 °C) |
| Density | 2.267 g/cm³ |
About Carbon
Carbon gets its own subdiscipline because it is the only element that catenates indefinitely with itself in chains, rings, sheets, and cages while still leaving valences free for nitrogen, oxygen, and the rest of the periodic table to plug in. The C–C single bond is 348 kJ/mol; the C=C double bond is 614 kJ/mol; sp, sp², and sp³ hybridization patterns let one element span everything from acetylene to diamond without changing identity. The allotropes alone are a working demonstration of how geometry sets properties: diamond (sp³, transparent insulator, hardest natural material), graphite (sp², semimetal, lubricant), graphene (one sp² sheet, ~130 GPa tensile strength), fullerenes (closed cages discovered by Kroto, Curl, and Smalley in 1985), nanotubes, and amorphous activated carbon with surface areas above 3000 m²/g. The ¹⁴C cosmogenic isotope produced by cosmic-ray neutrons hitting atmospheric ¹⁴N gives Libby radiocarbon dating its 50,000-year reach. Industrially, coke from metallurgical coal still reduces every ton of pig iron made in the world's blast furnaces, and CO₂ is the climate problem.
Fun Fact
Graphene is a single-atom-thick sheet of sp² carbon with about 200 times the tensile strength of steel and electron mobility above 200,000 cm²/V·s — properties so extreme that Geim and Novoselov got a Nobel five years after first peeling it off graphite with Scotch tape.
Common Uses
- Metallurgical coke for blast-furnace reduction of iron ore
- Carbon fiber composites in aerospace primary structure and wind blades
- Activated carbon for water treatment and solvent vapor recovery
- Synthetic and natural diamond for cutting, drilling, and abrasives
- Radiocarbon dating of organic material up to ~50,000 years old