P
30.974Phosphorus
Fosfor
Phosphorus is a reactive nonmetal with atomic number 15. It is essential in DNA, RNA, ATP, bones and teeth, and its compounds are widely used in fertilizers, matches, detergents, steel production and special glasses.
15
30.974 g/mol
[Ne] 3s² 3p³
2 | 8 | 5
2.19
1.82 g/cm³
44.15 °C
279.9 °C
Hennig Brand
Phosphorus was discovered by Hennig Brand in 1669 while experimenting with urine. Its name comes from Greek roots meaning light-bringer, because white phosphorus glows in the dark.
Phosphorus-31
Natural abundance: 100%. The only stable naturally occurring isotope of phosphorus.Phosphorus-32
Natural abundance: Synthetic. Half-life: About 14.3 days. Radioactive isotope used in biological and medical research.H₃PO₄
Phosphoric AcidUsed in fertilizers, food chemistry and phosphate production.Ca₃(PO₄)₂
Calcium PhosphateMajor mineral component of bones, teeth and phosphate rocks.P₄O₁₀
Phosphorus PentoxidePowerful dehydrating agent in chemistry.PCl₃
Phosphorus TrichlorideReactive chlorinating reagent and precursor for phosphorus chemicals.PCl₅
Phosphorus PentachlorideChlorinating reagent that illustrates expanded-valence phosphorus chemistry.Na₃PO₄
Sodium PhosphateUsed in cleaning, water treatment and phosphate chemistry.- Phosphate fertilizers for agriculture
- Red phosphorus on safety match striking surfaces
- Phosphates in some detergents, special glasses and ceramics
- Phosphorus compounds in steel production and chemical manufacturing
- White phosphorus in flares, smoke devices and specialized military applications
Phosphorus is essential for all living organisms. It forms part of DNA, RNA, ATP and phospholipids, and much of the phosphorus in the human body is stored as calcium phosphate in bones and teeth.
- White phosphorus glows faintly in the dark and is highly dangerous.
- Red phosphorus is much safer than white phosphorus and is used in safety matches.
- Black phosphorus has a layered structure and is studied as a two-dimensional semiconductor material.
- The negative charge of DNA comes from phosphate groups in its sugar-phosphate backbone.
- ATP, the main energy currency of cells, contains phosphate groups.
- Phosphorus has atomic number 15 and belongs to group 15.
- Its electron configuration is [Ne] 3s² 3p³.
- Phosphorus has five valence electrons and can form several oxidation states.
- PCl₅ is a classic example used to discuss expanded valence around a third-period central atom.
What is the atomic number of phosphorus?
The atomic number of phosphorus is 15.
What is the electron configuration of phosphorus?
Phosphorus has the electron configuration [Ne] 3s² 3p³.
Why is phosphorus important for life?
Phosphorus is found in DNA, RNA, ATP, phospholipids, bones and teeth.
What are the main allotropes of phosphorus?
The main phosphorus allotropes include white phosphorus, red phosphorus, black phosphorus and violet phosphorus.
What is the difference between white and red phosphorus?
White phosphorus is highly reactive and toxic, while red phosphorus is more stable and is used on safety match striking surfaces.
What is phosphorus used for?
Phosphorus is used in fertilizers, safety matches, phosphates, steel production, special glasses and chemical manufacturing.