Phosphorus (P)
Phosphorus (P) is element 15, a nonmetal. Atomic mass 30.973761998, configuration [Ne] 3s² 3p³. Properties, isotopes, oxidation states, uses and history, with an interactive 3D atom model.
Key facts
| Atomic number | 15 |
|---|---|
| Symbol | P |
| Standard atomic weight | 30.973761998(5) |
| Category | Other nonmetal |
| Group | 15 |
| Period | 3 |
| State at room temperature | Solid |
| Electron configuration | [Ne] 3s² 3p³ |
| Valence electrons | 5 |
| Common oxidation states | -3, +3, +5 |
| Common ions | P³⁻ |
| Electronegativity (Pauling) | 2.19 |
| First ionization energy | 1012 kJ/mol |
| Electron affinity | 72.04 kJ/mol |
| Atomic radius | 98 pm |
| Density | 1.823 g/cm³ |
| Melting point | 44.13°C |
| Boiling point | 280.50°C |
| Specific heat | 0.769 J/(g·°C) |
Natural isotopes
- P-31: Stable
Common uses
- Fertilizers
- Matchboxes (Red P)
- Steel production
Where it matters
- Agriculture (Essential fertilizer)
- Biology (DNA backbone/ATP)
- Eutrophication
Hazards
- P allotrope is highly toxic and pyrophoric (ignites in air)
History
| Discovered | 1669 |
|---|---|
| Discovered by | Hennig Brand |
| Name | Derived from Greek Light-bearing |