The periodic table/Phosphorus

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Discovery

Phosphorus was discovered in 1669 by Henning Brandt in Hamburg. The name is derived from the Greek word, Φωσφόρος (phosphoros), meaning light-bearer.

Quick Facts

Name: Phosphorus

Symbol: P

Mass: 30.97376

Atomic Number: 15

Electron Configuration: [Ne] 3s² 3p³

Classification: non-metal

CAS Number: 7723-14-0

Appearance: White phosphorus is a poisonous waxy solid that is spontaneously flammable and glows in the dark. Red phosphorous is an amorphous non-poisonous solid.

Discovery in: 1669

Key Isotopes: ³¹P

Allotropes: white P, red P, black P, P₂

Density: 1.82 g/L (diamond)

Crystal Structure: monoclinic

Melting Point: 44.15 °C

Boiling Point: 280.5 °C

Uses

White phosphorus is used in flares and incendiary devises. Red phosphorus is the material, when mixed with powdered glass, that is stuck on the side of boxes of safety matches where the matches must be struck to light them. However, by far the largest use of phosphorus is for fertilizers, mainly in the form of ammonium phosphate – they are manufactured from phosphate ores by conversion into phosphoric acids. Phosphorus is also important in the production of steel. Phosphates are ingredients of some detergents, but are increasingly being omitted nowadays due to concern that high phosphate levels in natural water supplies cause the growth of undesirable algae. Phosphates are also used in the production of special glasses and fine chinaware.

Phosphorus is essential to all living things since it forms the structural sugar-phosphate helices of DNA and RNA. It is the key to energy transfer in cells in the weakly bonded third phosphate group in ATP (adenosine-Tri-phosphate), and is present in several other biologically important molecules. We take in about 1 gram of phosphate a day, and we store about 750 grams in our bodies, since our bones and teeth are mainly calcium phosphate. White phosphorus is very toxic and contact with skin can cause severe burns.

Atomic Data

Atomic radius: 1.800 Å

Covalent radius: 1.09 Å

Electronegativity: 2.190

Electron affinity: 72.075 kJ mol^-1

Ionisation energies

First: 1011.811 kJ mol^-1

Second: 1907.465 kJ mol^-1

Third: 2914.115 kJ mol^-1

Fourth: 4963.578 kJ mol^-1

Fifth: 6273.963 kJ mol^-1

Sixth: 21267.377 kJ mol^-1

Seventh: 25430.619 kJ mol^-1

Eighth: 29871.836 kJ mol^-1

Supply Risk

Scarcity factor: 5.0 (medium risk)

Crustal abundance: 567 ppm

Reserve base distribution: 44.7%

Production concentration: 38.5%

Top 3 countries for mining:

Morocco
China
USA

Top 3 countries for production:

China
Mexico
Morocco

Oxidation States and Isotopes

Common oxidation states: 5, 3, -3

Isotopes

Isotope	Atomic mass	Abundance (%)	Half life	Mode of decay
³¹P	30.974	100

Pressure and Temperature Data

Molar heat capacity: 23.824 J mol^-1 K^-1