Oxygen - ASCII Periodic Table of the Elements

ASCII PERIODIC TABLE OF THE ELEMENTS

  O

Relative atomic mass: 15.9994 ± 0.0003

English: Oxygen
French: Oxygène
Croatian: Kisik
German: Sauerstoff
Italian: Ossigeno
Spanish: Oxígeno

Atomic number: 8
Group numbers: 16
Period: 2
Standard state (20 °C): gas

Discovery: 1772 Carl William Scheele (SE)

Oxygen was discovered by Carl William Scheele (SE) in 1772. The origin of the name comes from the Greek words 'oxy genes' meaning 'acid' and 'forming' (acid former). It is a colourless, odourless gas; pale blue liquid. Oxygen is extremely reactive and forms oxides with nearly all other elements except noble gases. It is the most abundant element in the earth's crust and makes up almost 21% of the atmosphere. Oxygen is obtained primarily from liquid air by fractional distillation. Small amounts are made in the laboratory by electrolysis of water. Oxygen is used in steel making, welding and supporting life. Naturally occurring ozone (O3) in the upper atmosphere shields the earth from ultraviolet radiation.

Electronic configuration: [He] 2s² 2p⁴
Formal oxidation number: -2
Atomic radius: 60.4 pm

Electronegativities: 3.44
Thermal conductivity: 0.0263 W/(m K)
Electrical resistivity (20 °C): - μΩcm

Melting point: -218.7916 °C
Boiling point: -182.95 °C

Heat of fusion: 0.444 kJ/mol
Heat of vaporization: 6.82 kJ/mol
Heat of atomization: 246.785 kJ/mol