Phosphorus occurs in several elemental forms and in many essential compounds. Phosphates contribute to bones, genetic material, and cellular energy transfer. They are also major fertilizer ingredients. Red phosphorus on a safety-match striking surface offers a familiar example of an elemental form with a separate role.
FROM ELEMENT TO APPLICATION
AN ELEMENT IN CONTEXT
Why does a safety-match system separate the striking surface from the match head?
Red phosphorus in a formulated coating
FOLLOW THIS RELATIONSHIP
Separate reactive components
A safety match places red phosphorus in the striking surface while the match head supplies other parts of the designed ignition system.
Explore the model (optional)
PFORM → INTERACTION → CONSEQUENCE
Follow the explanation in either direction. These are authored steps, not a physical clock.
Atomic identity, reference properties and structure models
INTERACTIVE 3D15 visible sites
An electron censusDrag to rotate · scroll or pinch to zoom
[Ne] 3s2 3p3. Grouping electrons by principal shell connects the neutral-atom configuration to periodic-table patterns.
What this representation means
A three-dimensional counting diagram. Dots are count markers, not measured electron positions; spherical placement and spacing are arbitrary. There are no electron trajectories here. Orbitals describe quantum states.
Hennig Brand's search for valuable substances led him to isolate phosphorus in Hamburg in 1669. The luminous material became a curiosity, and knowledge of its preparation gradually spread beyond its discoverer. Later production from phosphate-bearing materials supported a growing chemical industry. During the nineteenth century, matches made phosphorus chemistry conspicuous in everyday life while exposing the very different consequences of using different forms.
1669
Element isolated
Brand isolated phosphorus through alchemical investigation.
19th century
Match manufacture expanded
Match production brought phosphorus into industrial manufacture.
Phosphorus occurs naturally in combined forms, especially phosphate such as apatite. It is also part of biological compounds and the mineral material of bones and teeth. Phosphate rock provides an industrial source, linking mineral extraction with the manufacture of chemicals that supply phosphorus to other systems.
Phosphorus has several , including white, red, and black forms, with markedly different structures and reactivities. White phosphorus reacts particularly readily with air. A phosphate compound is different again: its phosphorus is chemically bonded to oxygen, so neither its properties nor its hazards can be inferred from white phosphorus alone.
Each section links its supporting references. Descriptions and diagrams were authored for this atlas. Source checks completed. Source checks dated 2026-09-06.
CITE THIS PAGE
Family labels and the group-3 layout are teaching conventions. A table position does not establish an unknown bulk property. Electronic configurations refer to neutral atoms; ions and material environments require their own account.
Read each reference property together with its units, conditions and the reference information below.
Not yet recorded: electron affinity, second ionization energy, ground-state term symbol, van der waals radius, thermal conductivity, specific heat capacity, electrical resistivity, crystal structure, lattice parameter a, space group, abundance in seawater, abundance in the universe, annual production, supply-risk listing, hazard classification, biological role, cas registry number, pubchem cid, wikidata item. These families are declared and awaiting an ingestion run against the source each names; they are listed here rather than shown as empty rows.
Physical
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Phase at 20 °C
solid
293.15 K, 101.325 kPa
Melting point in K
317.3 K
at standard pressure unless noted Value for white phosphorus; other allotropes differ.
Boiling point in K
553.7 K
101.325 kPa
Density in g/cm³
1.82 g/cm³
solids and liquids at 293 K; gases at 273 K and 101.325 kPa Value for white phosphorus.
Atomic and electronic
Intended reference: Pauling electronegativity scale · Widely tabulated; original in The Nature of the Chemical Bond
Electronegativity in Pauling
2.19 Pauling
Pauling scale
First ionization energy in kJ/mol
1012 kJ/mol
gas-phase neutral atom, ground state
Covalent radius in pm
107 pm
single-bond covalent radius
Common oxidation states
-3, +3, +5
states met in ordinary compounds; not exhaustive
Occurrence and identity
Intended reference: CRC Handbook of Chemistry and Physics · CRC Press
Abundance in the crust in mg/kg
1050 mg/kg
upper continental crust, mass fraction
Has stable isotopes
Yesderived
Discovery year in CE
1669 CEderived
WHERE IT SITS AMONG ITS NEIGHBORS
Electronegativity across period 3
P 2.19 Pauling · Phosphorus
Electronegativity across period 3. Exact values.
Na
0.93
Mg
1.31
Al
1.61
Si
1.9
P
2.19
S
2.58
Cl
3.16
Electronegativity down group 15
P 2.19 Pauling · Phosphorus
Electronegativity down group 15. Exact values.
N
3.04
P
2.19
As
2.18
Sb
2.05
Bi
2.02
The trend uses the same reference-property values as the periodic table. Elements with no recorded value are left out of the line rather than drawn at zero.
