Carbon
Carbon is a member of group 14 of the periodic table. It has three allotropic forms of it, diamonds, graphite and fullerite. Carbon-14 is commonly used in radioactive dating. Carbon occurs in all organic life and is the basis of organic chemistry. Carbon has the interesting chemical property of being able to bond with itself, and a wide variety of other elements.
Gallery
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Emission spectrum
Physical Propertiesmass · density · phase · crystal
Atomic Mass
12.0110Da
Density
2.2000g/cm³
Phase (STP)
Solid
Melting Point
—
Boiling Point
4098.1K
Molar Heat
0.7090J/(mol·K)
Crystal Structure
DIA
Lattice Constant
3.570Å
Atomic Radiiatomic · covalent · van der Waals
Atomic (Empirical)
70.00pm
Covalent
75.00pm
Van der Waals
170.00pm
Electronic Propertieselectronegativity · ionization · affinity
Electron Configuration
[He] 2s2 2p2
Electron Shells
2, 4
Electronegativity
2.55Pauling
Electron Affinity
1.3kJ/mol
1st Ionization Energy
11.3kJ/mol
Oxidation States
-4, -3, -2, -1, 0, +1, +2, +3, +4
Orbital DiagramAufbau · Hund's rule · Pauli exclusion
Full: 1s2 2s2 2p2Short: [He] 2s2 2p2
Ionization Energies (6 known)
Emission Spectrumvisible range · characteristic spectral lines
Abundanceby mass
Log scale · ppm = parts per million by mass
Biological Role
Backbone of all organic life. Forms proteins, DNA, carbohydrates, and lipids.
Discovery
Discovered By
Known to the ancients
Named By
—
Year
—
Nuclear Data
Known Isotopes
16
Stable Isotopes
4
Stable Mass Numbers
12, 13, 21, 23
Natural isotopic abundance (IUPAC recommended values)
Isotopes of C16 known
| Nuclide | Z | N | Mass (AMU) | Half-life | Decay | Jπ | Abundance |
|---|---|---|---|---|---|---|---|
| 8C | 6 | 2 | 8.037643 | 3.50 zs | 2p (1%) | 0+ | — |
| 9C | 6 | 3 | 9.031037 | 126 ms | β⁺ (1%), β⁺p (0.075%), β⁺α (0.384%) | 3/2- | — |
| 10C | 6 | 4 | 10.016853 | 19.3 s | β⁺ (1%) | 0+ | — |
| 12Cstable | 6 | 6 | 12.000000 | Stable | stable (1%) | 0+ | 9894.0000% |
| 13Cstable | 6 | 7 | 13.003355 | Stable | stable (1%) | 1/2- | 106.0000% |
| 21Cstable | 6 | 15 | 21.049000 | Stable | n | 1/2+ | — |
| 22C | 6 | 16 | 22.057554 | 6.20 ms | β⁻ (1%), β⁻n (0.61%), 2n (0.37%) | 0+ | — |
| 23Cstable | 6 | 17 | 23.068890 | Stable | n | 3/2+ | — |
Key Compoundscontaining C
CO₂
Carbon Dioxide
A linear triatomic molecule produced by combustion and respiration
CO
Carbon Monoxide
A colorless, odorless, poisonous gas
CaCO₃
Calcium Carbonate
The main component of limestone, marble, chalk, and seashells
NaHCO₃
Sodium Bicarbonate
Baking soda — a mild alkali that decomposes to Na₂CO₃, H₂O, and CO₂ when heated
CH₄
Methane
The simplest alkane with perfect tetrahedral geometry
C₂H₆
Ethane
The second simplest alkane with a C–C single bond allowing free rotation
C₃H₈
Propane
A three-carbon alkane commonly used as LPG fuel for heating and cooking
C₂H₄
Ethylene
The simplest alkene with a C=C double bond and planar geometry
C₂H₂
Acetylene
The simplest alkyne with a C≡C triple bond and linear geometry