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Oxidation & Electrons | Appearance & Characteristics Reactions | Compounds | Radius | Conductivity Abundance & Isotopes 
Red phosporus enables matches to strike. |
General:
| Name: Phosphorus | Symbol: P |
| Type: Non-Metal, Nitrogen group | Atomic weight: 30.97376 |
| Density @ 293 K: 1.82 g/cm3 | Atomic volume: 17.0 cm3/mol |
| Discovered: Hennig Brand discovered phosphorus in 1669, preparing it from urine, which naturally contains considerable quantities of dissolved phosphates. The name comes from the Greek word 'phosphoros', meaning bringer of light. | |
States
| State (s, l, g): solid | |
| Melting point: 317.3 K (44.2 oC) | Boiling point: 553.7 K (280.5 oC) |
Energies
| Specific heat capacity: 0.77 J g-1 K-1 | Heat of atomization: 315 kJ mol-1 |
| Heat of fusion: 0.657 kJ mol-1 | Heat of vaporization (sublimation): 12.129 kJ mol-1 |
| 1st ionization energy: 1011.7 kJ mol-1 | 2nd ionization energy: 1903.2 kJ mol-1 |
| 3rd ionization energy: 2911.9 kJ mol-1 | Electron affinity: 72.07 kJ mol-1 |
Oxidation & Electrons
| Shells: 2,8,5 | Electron configuration: [Ne] 3s2 3p3 |
| Minimum oxidation number: -3 | Maximum oxidation number: 5 |
| Min. common oxidation no.: -3 | Max. common oxidation no.: 5 |
| Electronegativity (Pauling Scale): 2.19 | Polarizability volume: 3.6 Å3 |
Appearance & Characteristics
| Structure: special P4 tetrahedral arrangement (white phosphorus) | Color: pale yellow |
| Harmful Effects: White phosphorus is very toxic and contact with skin can cause severe burns. | Hardness: 0.5 mohs |
| Characteristics: White phosphorus is a highly reactive, waxy, white-yellow, transparent solid with acrid fumes. It emits a faint greenish glow (luminescence) upon uniting with oxygen. It is insoluble in water, but soluble in carbon disulfide. White phosphorus ignites spontaneously in air, burning to the pentoxide (P4O10). Phosphorus exists in two other main allotropic forms: red, and black (or violet). Red phosphorus is formed by heating white phosphorus to 250 oC or by exposing white phosphorus to sunlight. Black phosphorus is the least reactive allotrope and has a structure resembling that of graphite. | |
| Uses: Being an essential plant nutrient, the main use of phosphorus -via phospate compounds - is in the production of fertilizers. Phosphorus is used in the manufacture of safety matches (red phosphorus), pyrotechnics and incendiary shells. Phosphorus is also important in steel production, in the making of phosphor bronze, and in many other related products. Phosphates are ingredients of some detergents. | |
Reactions
| Reaction with air: vigorous, ⇒ P4O10 ignites | Reaction with 6 M HCl: none |
| Reaction with 3 M HNO3: mild, ⇒ NOx, | Reaction with 6 M NaOH: mild, ⇒ PH3 (phosphine) may ignite |
Compounds
| Oxide(s): P4O10, P4O6 | Chloride(s): PCl3, PCl5, P2Cl4 |
| Hydride(s): PH3, P2H4 + more |
Radius
| Atomic radius: 100 pm | Ionic radius (1+ ion): pm |
| Ionic radius (2+ ion): pm | Ionic radius (3+ ion): 58 pm |
| Ionic radius (2- ion): pm | Ionic radius (1- ion): pm |
Conductivity
| Thermal conductivity: 0.24 W m-1 K-1 | Electrical conductivity: 1.0 x 10-11 S cm-1 |
Abundance & Isotopes
| Abundance earth's crust: 1,000 ppm by weight, 700 ppm by moles | |
| Abundance solar system: 7 ppm by weight, 300 parts per billion by moles | |
| Cost, pure: 4 $/100g | |
| Cost, bulk: $/100g | |
| Source: Phosphorus is never found free in nature, but it is widely distributed in many different minerals. Phosphorus is produced commercially from calcium phosphate (phosphate rock). Calcium phosphate is heated in a furnace with silica and carbon to produce vaporized tetraphosphorus, which is then condensed into phosphorus as a white powder under water to prevent oxidation. | |
| Isotopes: Phosphorus has 18 isotopes whose half-lives are known, with mass numbers 26 to 43. Of these only one is stable 31P. | |
