Phosphorous

Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). With few exceptions, minerals containing phosphorus are in the maximally oxidized state as inorganic phosphate rocks.

Characteristics

Phosphorus is a nonmetal that is not found free in nature but it is widely distributed in many different minerals. It is a crucial component of life. It is used in fertilizers, detergents, foods, and drinks. It is a very poisonous and volatile white solid that glows in the dark, and is spontaneously flammable in air.

History

Phosphorus was first isolated as white phosphorus in 1669. It was originally used in the manufacture of gunpowder, fertilizers, incendiaries, matches, pesticides, toothpaste and in the treatment of metals. The vast majority of phosphorus compounds are consumed as fertilizers. Other applications include the role of organophosphorus compounds in detergents, pesticides, and nerve gases.

Occurrence and Production

Phosphorus is not found free in nature, but it is widely distributed in many minerals, primarily phosphate rock. Large deposits of apatite are located in China, Russia, Morocco, Florida, Idaho, Tennessee, Utah, and elsewhere.

Applications

Phosphorus is used in the manufacture of safety matches (red phosphorus), pyrotechnics and incendiary shells. Phosphorus is also used in steel manufacture and in the production of phosphor bronze. It is also used in numerous other applications, including the production of semiconductors, the removal of sulfur from metals, and the making of pesticides and water treatment products.

Biological Role

Phosphorus is an essential element for life. As phosphate, it is a component of DNA, RNA, ATP, and also the phospholipids, which form all cell membranes. Demonstrating the link between phosphorus and life, elemental phosphorus was historically first isolated from human urine, and bone ash was an important early phosphate source.

See Also

• Phosphate
• Phosphoric Acid
• Phosphorus Cycle
• Phosphorus Pentoxide