Oxygen has an atomic number of 8, meaning each atom contains 8 protons in its nucleus.
The standard atomic weight of oxygen is 15.999 u (unified atomic mass units).
Oxygen is classified as a reactive nonmetal.
Oxygen is a gas at 20 Β°C (68 Β°F).
The melting point of oxygen is -218.79 Β°C / 54.36 K.
The boiling point of oxygen is -182.96 Β°C / 90.19 K.
The density of oxygen is 1.31e-3 g/cmΒ³ (20Β°C).
Oxygen has a Pauling electronegativity of 3.44.
The electron configuration of oxygen is [He] 2s2 2p4.
Oxygen commonly exhibits the following oxidation states: β2.
Oxygen was discovered in 1774 by Joseph Priestley; Carl Wilhelm Scheele.
Oxygen is a stable element with no naturally occurring radioactive isotopes.
Essential for aerobic respiration in most complex organisms.
Oxygen is used for: Medical oxygen; Steelmaking; Water treatment; Rocket oxidizers.