Oxygen was discovered by English chemist Joseph Priestley and Swedish chemist Carl Wilhelm Scheele in 1774 in England, Sweden.
Name: Oxygen Symbol: O Atomic number: 8 Atomic weight: 15.999 State: gas Group, period, block: 16, 2, p Color: colorless gas, pale blue liquid Classification: Non-metallic Electron configuration: 1s2 2s2 2p4
Density: 1495 kg m-3 or 1.429 g/L Melting point: 54.8 [or -218.3 °C (-360.9 °F)] K Boiling point: 90.2 [or -182.9 °C (-297.2 °F)] K
Oxidation states: 2, 1, -1, -2 Electronegativity: 3.44 (Pauling scale) Ionization energies: 1st: 1313.9 kJ·mol-1 Covalent radius: 66±2 pm Van der Waals radius: 152 pm
There are three naturally occurring isotopes of oxygen exist, 16O, 17O, and 18O.