|Type:Non-Metal, Chalcogen||Atomic weight:15.9994|
|Density @ 293 K:0.001429 g/cm3||Atomic volume:14.0 cm3/mol|
Oxygen was discovered in 1774 by Joseph Priestley in England and two years earlier, but unpublished, by Carl W. Scheele in Sweden.
|State (s, l, g):gas|
|Melting point:54.8 K (-218.3 °C)||Boiling point:90.2 K (-182.9 °C)|
|Specific heat capacity:0.918 J g-1 K-1||Heat of atomization:249 kJ mol-1|
|Heat of fusion:0.444 kJ mol-1 of O2||Heat of vaporization :6.82 kJ mol-1 of O2|
|1st ionization energy:1313.9 kJ mol-1||2nd ionization energy:3388.2 kJ mol-1|
|3rd ionization energy:5300.3 kJ mol-1||Electron affinity:140.97875 kJ mol-1|
|Shells:2, 6||Electron configuration:[He] 2s2 2p4|
|Minimum oxidation number:-2||Maximum oxidation number:25|
|Min. common oxidation no.:-2||Max. common oxidation no.:0|
|Electronegativity (Pauling Scale):3.44||Polarizability volume:0.793 Å3|
O2 is non-toxic under normal conditions. However, exposure to oxygen at higher than normal pressures, e.g. scuba divers, can lead to convulsions. Ozone (O3) is toxic and if inhaled can damage the lungs.
Oxygen in its common form (O2) is a colorless, odorless and tasteless diatomic gas. Oxygen is extremely reactive and forms oxides with nearly all other elements except noble gases.
The major commercial use of oxygen is in steel production. Carbon impurities are removed from steel by reaction with oxygen to form carbon dioxide gas. Oxygen is also used in oxyacetylene welding, as an oxidant for rocket fuel, and in methanol and ethylene oxide production.
|Reaction with air:none||Reaction with 6 M HCl:none|
|Reaction with 15 M HNO3:none||Reaction with 6 M NaOH:none|
|Oxide(s):O2, O3||Chloride(s):Cl2O, ClO2|
|Atomic radius:60 pm||Ionic radius (1+ ion):pm|
|Ionic radius (2+ ion):pm||Ionic radius (3+ ion):pm|
|Ionic radius (2- ion):126 pm||Ionic radius (1- ion):pm|
|Thermal conductivity:0.02583 W m-1 K-1||Electrical conductivity: S cm-1|
|Abundance earth's crust:46 % by weight, 60 % by moles|
|Abundance solar system: 9,000 ppm by weight, 700 ppm by moles|
|Cost, pure:$0.3 per 100g|
|Cost, bulk:$0.02 per 100g|
Oxygen is the most abundant element in the Earth's crust, accounting for almost half of it by mass. More than half of the atoms in the Earth's crust are oxygen atoms. About 86 percent of the mass of Earth's oceans is oxygen - mainly in the form of water. Oxygen is the third most common element in the Universe, behind hydrogen and helium. It is obtained commercially from liquefied air separation p
13 whose half-lives are known, with mass numbers 12 to 24. Of these, three are stable: 16O, 17O and 18O.