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Technical data for Oxygen

Click any property name to see plots of that property for all the elements.

Overview
NameOxygen
SymbolO
Atomic Number8
Atomic Weight15.9994
Density1.429 g/l[note]
Melting Point-218.3 °C
Boiling Point-182.9 °C

Thermal properties
PhaseGas
Melting Point-218.3 °C
Boiling Point-182.9 °C
Absolute Melting Point54.8 K
Absolute Boiling Point90.2 K
Critical Pressure5.043 MPa (49.77 Atm)
Critical Temperature154.59 K
Heat of Fusion0.222 kJ/mol
Heat of Vaporization3.41 kJ/mol
Heat of CombustionN/A
Specific Heat919 J/(kg K)[note]
Adiabatic Index7/5
Neel PointN/A
Thermal Conductivity0.02658 W/(m K)
Thermal ExpansionN/A

Bulk physical properties
Density1.429 g/l[note]
Density (Liquid)N/A
Molar Volume0.011196
Brinell HardnessN/A
Mohs HardnessN/A
Vickers HardnessN/A
Bulk ModulusN/A
Shear ModulusN/A
Young ModulusN/A
Poisson RatioN/A
Refractive Index1.000271
Speed of Sound317.5 m/s
Thermal Conductivity0.02658 W/(m K)
Thermal ExpansionN/A

Reactivity
Valence2
Electronegativity3.44
ElectronAffinity141 kJ/mol
Ionization Energies
1313.9, 3388.3, 5300.5, 7469.2, 10989.5, 13326.5, 71330, 84078 kJ/mol

Health and Safety
Autoignition PointN/A
FlashpointN/A
Heat of CombustionN/A
DOT Hazard Class2.2
DOT Numbers1073
EU NumberN/A
NFPA Fire Rating0
NFPA Hazards
Oxidizing Agent
NFPA Health Rating3
NFPA Reactivity Rating2
RTECS NumberRTECSRS2060000
NFPA LabelNFPA Label

Classifications
Alternate NamesNone
Names of Allotropes
Dioxygen, Ozone, Tetraoxygen
Blockp
Group16
Period2
Electron Configuration[He]2s22p4
ColorColorless
Discovery
1774 in Sweden and United Kingdom
Gas phaseDiatomic
CAS NumberCAS7782-44-7
CID NumberCID977
Gmelin NumberN/A
NSC NumberN/A
RTECS NumberRTECSRS2060000

Electrical properties
Electrical TypeN/A
Electrical ConductivityN/A
ResistivityN/A
Superconducting PointN/A

Magnetic properties
Magnetic TypeParamagnetic
Curie PointN/A
Mass Magnetic Susceptibility1.335×10-6
Molar Magnetic Susceptibility4.27184×10-8
Volume Magnetic Susceptibility1.90772×10-6

Abundances
% in Universe1%
% in Sun0.9%
% in Meteorites40%
% in Earth's Crust46%
% in Oceans86%
% in Humans61%

Atomic dimensions and structure
Atomic Radius48 pm
Covalent Radius73 pm
Van der Waals Radius152 pm
Crystal StructureBase Centered Monoclinic
Lattice Angles
π/2, 2.313085, π/2
Lattice Constants
540.3, 342.9, 508.6 pm
Space Group NameC12/m1
Space Group Number12

Nuclear Properties
Half-LifeStable
LifetimeStable
Decay ModeN/A
Quantum Numbers3P2
Neutron Cross Section0.00028
Neutron Mass Absorption1×10-6
Known Isotopes
12O, 13O, 14O, 15O, 16O, 17O, 18O, 19O, 20O, 21O, 22O, 23O, 24O, 25O, 26O, 27O, 28O
Stable Isotopes
16O, 17O, 18O
Isotopic Abundances
16O99.757%
17O0.038%
18O0.205%


Notes on the properties of Oxygen:

Density: Density given for O at 0° Celsius. 2

Specific Heat: Value given for gas phase of O . 2

Up to date, curated data provided by
Mathematica's ElementData function from Wolfram Research, Inc.

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