8
O
15.999
Oxygen
Element 8 · 15.999 u · p-block
nonmetal
The most abundant element in Earth's crust. Essential for respiration in most living organisms.
Phase (STP)
Gas
Melting Point
-218.79 °C
Boiling Point
-182.96 °C
Density
0.001429 g/cm³
Electronegativity
3.44
Atomic Radius
60 pm
Ionization Energy
1314 kJ/mol
Electron Affinity
141 kJ/mol
Discovered
1774 · Joseph Priestley
Electron Configuration
[He] 2s2 2p4
Electron Orbitals
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