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Element 8 - Oxygen (O) sound

From oxys and gen, or acid-forming; discovered 1774; the most abundant element, making up about half of everything on earth, 21 percent of the atmosphere by volume and two thirds of the human body. Breathed in by animals, oxygen is restored to the air by plants.

Properties

Atomic Number: 8
Atomic Weight: 15.9994
Electron Configuration (at ground state): 1s22s22p4
Oxidation States (Bold most stable): -2
Boiling Point (K): 90.188
Melting Point (K): 54.8
Density (at STP -- g/l): 1.429
Atomic Volume (liquid state at boiling point -- cm3/mol) 14.0
Number of stable isotopes: 3
Covalent Radius (Å): 0.73
Atomic Radius (Å): 0.65
First Ionization Potential (V): 13.618
Electronegativity (Pauling's): 3.44
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.92
Heat of Vaporization (kJ/mol): 3.4109
Heat of Fusion (kJ/mol): 0.222
Thermal Conductivity (at 300K -- W m-1 K-1): 0.2674
Crystal Structure: Cubic