Oxygen is a chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. After hydrogen and helium, It is the third-most abundant element in the universe by mass. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with formula O2. Diatomic oxygen gas constitutes 20.95% of the Earth’s atmosphere. O makes up almost half of the Earth’s crust in the form of oxides.
|Atomic Mass||15.999 g.mol-1|
|Discovered by||Joseph Priestly in 1774|
The name oxygen was coined in 1777 by Antoine Lavoisier, who first recognized O as a chemical element and correctly characterized the role it plays in combustion. Common uses of O include production of steel, plastics, and textiles, brazing, welding and cutting of steel and other metals, rocket propellant, O therapy, and life support systems in aircraft, submarines, spaceflight, and diving.
Characteristics of Oxygen
- The gas is colorless, odorless, and insipid in a normal state. Liquid oxygen is slightly paramagnetic. It is reactive and forms oxides with every element except helium, neon, krypton, and argon. It is moderately soluble in water.
- Dioxygen is one of the common allotropes of O.
- Trioxygen is the most reactive allotrope of oxygen that would cause damage to lung tissue. This allotrope is termed ozone.
Uses of O
- It is used in the production and manufacturing of glass and stone products, and mining.
- Special O chambers are used in case of high pressure to increase the partial pressure of oxygen around the patient.
- The primary applications of oxygen include melting, refining, and manufacture of steel along with other metals.