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Atomic Number	8

Atomic Symbol	O

Atomic Weight	15.9994 amu

Group	Non-Metal, 16

Form	Gas

Density @ STP	1.404 g/L

Melting Point	-218.79 °C (-361.82 °F, 54.36 °K)

Boiling Point	-182.95 °C (-297.31 °F, 90.2 °K)

Heat of Fusion	0.44 kJ/mol

Heat of Vaporization	6.82 kJ/mol

First Ionization Potential	13.61806 eV

Electronegativity (on Pauling scale	3.44

Specific Heat Capacity	0.918 J/g K

Ground State Electron Configuration	2p⁴

Oxidation State(s)	-2

Stable Isotopes and Natural Abundance on Earth	¹⁶O, 99.762%; ¹⁷O, 0.038%; ¹⁸O, 0.200%

Selected Radioisotopes	¹⁵O

Atomic Radius	48 pm

Crystal Structure	Monoclinic

Discovered by	Priestly, 1774