What is Phosphorus?

Phosphorus in Periodic Table

Chemistry Topics
Periodic Table Elements
4 min readMar 21, 2024


Phosphorus is a chemical element or member of group 15 in the periodic table with atomic number 15 and the symbol P. It is a member of the nitrogen family in the periodic table that lies below nitrogen and above arsenic.

Phosphorus in the periodic table with symbol P, atomic number 15, and electron configuration
Phosphorus in the periodic table

The uncombined form of phosphorus is not found in nature but combined forms are widely found in minerals. Phosphorus is an essential part of all living things (plants and animals) and forms the sugar-phosphate backbone of DNA and RNA molecules.


Phosphorus has two main forms such as white phosphorus and red phosphorus. White phosphorus is a poisonous waxy solid and contact with the skin can cause severe burns but red phosphorus is an amorphous non-toxic solid.

Phosphorus is a member of group 15 elements with three valence electrons in its outer quantum cell.

  • Element Symbol: P
  • Atomic Number: 15
  • Atomic Weight: 30.974
  • State at 20°C: Solid
  • Appearance: White, red, and violet are waxy, and black is metallic-looking
  • Melting point: 44.15°C, 111.47°F, 317.3 K
  • Boiling point: 280.5°C, 536.9°F, 553.7 K
  • Density (g/cm3): 1.823 (white)
  • Oxidation States: 5, 3, -3
  • CAS number: 7723–14–0
  • Chem Spider ID: 4575369

Phosphorus plays an important role in various biological reactions such as how the body uses carbohydrates and fats. It may also be important for the body to make protein.

Facts About Phosphorus

  • Phosphorus (symbol P) is a chemical element with an atomic number of 15. Therefore, the atomic structure of phosphorus contains 15 protons and 15 electrons.
  • The uncombined form of phosphorus is not found in nature but it is widely found in various phosphorus-containing rocks and minerals.
  • White phosphorus is made industrially by heating phosphate rock in the presence of carbon and silica in a furnace while red phosphorus is made by gently heating white phosphorus to about 250°C in the absence of air.
  • Phosphates are essential substances in the human body because they are part of genetic materials such as DNA and RNA. It can also be commonly found in plants. It is the main component in the formation of bones and teeth of the human body.
  • There are four forms of phosphorus (white, black, red, and violet) usually used these days.
  • Too much or too little phosphate can cause problems in human health such as kidney damage and osteoporosis.
  • In pure form, phosphorus is in white colour and most dangerous source of phosphorus known to us. While white phosphorus occurs in nature, it is extremely toxic and causes serious risks to our health.
  • Phosphorus is an essential plant nutrient and is used mainly in the manufacture of fertilizers. It is also used in the manufacture of safety matches (red phosphorus), pyrotechnics, and inflammatory shells.
  • Except for black phosphorus, other forms are a poor conductor of heat and electricity. All forms of the element are stable at room temperature. The white form is similar to yellow colour wax but the red and purple forms are non-crystalline solids and the black form is equivalent to graphite in pencil lead.

Uses of Phosphorus

Phosphorus is an important chemical element that is used for various commercial purposes and is essential to all living things. In biochemistry, it forms the sugar-phosphate backbone of DNA and RNA molecules. The most common applications of phosphorus are listed below:

  • White phosphorus compounds are used commonly as flame-retardant material and coatings material.
  • The first striking matchboxes by white phosphorus were invented by Charles Sauria in 1830. The materials by which matchboxes were made were poisonous to the workers, toxic if ingested, and hazardous. Presently, we use red phosphorus in the material stuck on the side of matchboxes.
  • Phosphorus is an essential plant nutrient that is involved in energy transfers, the strength of roots and stems, photosynthesis, the formation of seeds and flowers, and other important factors affecting overall plant health and growth. Therefore, phosphorus compounds are widely used for making various types of fertilizers such as ammonium phosphate. For making ammonium phosphate fertilizer from phosphate ores, the ores are first converted into phosphoric acids.
  • For making and acidifying foods and beverages, we use food-grade phosphoric acid which gives a tangy or sour taste of various colas and jams. Phosphoric acid is also used as a preservative of foods.
  • Phosphorus is an important component in the production of steel, phosphor bronze, and many other related products. It is added to metallic copper during its smelting process.
  • In some countries, sodium tripolyphosphate made from phosphoric acid is used for making detergents in some countries but banned in many others. It is an important component in water softening. Therefore, it enhances the performance of the detergents and prevents pipe/boiler tube corrosion.
  • It may used for the production of fine chinaware and special glasses.


Phosphorus — Element information, properties, and uses — Rsc.org

Phosphorus — Element, Symbol, Properties, Compounds, Uses — Priyamstudycentre.com

Phosphorus — Wikipedia.org

Phosphorus | Definition, Uses, & Facts | Britannica.com



Chemistry Topics
Periodic Table Elements

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