15
P
Phosphorus
30.973761998
Phosphorus (P)
NonmetalGroup 15Period 3p-block-block
Phosphorus is a chemical element with symbol P and atomic number 15. As an element, phosphorus exists in two major forms—white phosphorus and red phosphorus—but due to its high reactivity, phosphorus is never found as a free element on Earth. Instead phosphorus-containing minerals are almost always present in their maximally oxidised state, as inorganic phosphate rocks.
Latin name: Phosphorus
Atomic Number
15
Atomic Mass
30.973761998 g/mol
Phase (STP)
Solid
Electron Config.
[Ne] 3s² 3p³
General
SymbolP
Atomic Number15
Atomic Mass30.973761998 g/mol
CategoryNonmetal
Group15
Period3
Blockp-block
Electron Configuration[Ne] 3s² 3p³
Valence Electrons5
ColourWaxy white, yellow, scarlet, red, violet, black
Appearancecolourless, waxy white, yellow, scarlet, red, violet, black
CAS NumberCAS7723-14-0
Physical Properties
Phase (STP)Solid
Density1.82 g/cm³
Melting Point44.15°C · 111.47°F · 317.30 K
Boiling Point280.50°C · 536.90°F · 553.65 K
Atomic Properties
Atomic Radius98 pm
Covalent Radius107 pm
Van der Waals Radius180 pm
Electronegativity2.19 Pauling
Ionization Energy1012 kJ/mol
Electron Affinity72 kJ/mol
Oxidation States-3, -2, -1, +1, +2, +3, +4, +5
Ion ChargeP³⁻/P⁵⁺
Thermodynamic
Molar Heat23.824 J/(mol·K)
Electromagnetic
Electrical TypeInsulator
Crystal Structure
Crystal StructureOrthorhombic
Mechanical Properties
Mohs Hardness0
Abundance
In Universe0.0007%
In Sun0.00006999999999999999%
In Earth's Crust0.1100%
In Oceans0.000006%
In Humans1.1000%
In Meteorites0.1000%
Discovery & History
Discovery Year1669
Discovered ByHennig Brand
Isotopes of Phosphorus
| Isotope | Abundance | Half-life | Decay |
|---|---|---|---|
| P-31 | 100% | Stable | — |
| P-32 | — | 14.263 days | β⁻ |
| P-33 | — | 25.34 days | β⁻ |