Oxygen

Oxygen (O)

A colourless, odourless gaseous element belonging to group 16 of the periodic table. It is the most abundant element present in the earth's crust. It also makes up 20.8% of the Earth's atmosphere. For industrial purposes, it is separated from liquid air by fractional distillation. It is used in high temperature welding, and in breathing. It commonly comes in the form of Oxygen, but is found as Ozone in the upper atmosphere. It was discovered by Priestley in 1774.
Atomic Number8
Atomic Weight15.999
Mass Number16
Group16
Period2
Blockp
Protons8 p+
Neutrons8 n0
Electrons8 e-
Liquid oxygen in a beaker 4.jpg 8 oxygen (O) Bohr model.png Animated Bohr Model Enhanced Bohr Model Bohr Model Orbital Diagram

Properties

Atomic Radius
60 pm
Atomic Volume
Covalent Radius
63 pm
Metallic Radius
Ionic Radius
135 pm
Crystal Radius
121 pm
Van der Waals radius
152 pm
Density
0.001308 g/cm³
Boiling Point
90.19 K
Melting Point
54.8 K
Electrons per shell2, 6
Electronegativity
3.44
Electrophilicity
2.3379781748238 eV/particle
Proton Affinity
485.2 kJ/mol
Electron Affinity
1.4611135 eV/particle
Ionization Potential
13.618054 eV/particle
Heat of Vaporization
Heat of Fusion
Heat of Formation
249.229 kJ/mol
Molar Heat Capacity
29.378 J/(mol K)
Specific Heat Capacity
0.918 J/(g⋅K)
Thermal Conductivity
0.027 W/(m K)
Gas Basicity
459.6 kJ/mol
Dipole Polarizability
5.3 a₀
C6 Dispersion Coefficient
15.6 a₀
Oxidation States-2, -1, 1, 2
Color
Colorless
Crystal StructureBase Centered Monoclinic (CUB)
Lattice Constant
6.83 Å
Bulk Modulus
Electrical Resistivity
Electron Configuration[He] 2s2 2p4
Magnetic Ordering
Magnetic Susceptibility
PhaseGas
Poisson Ratio
Shear Modulus
Young's Modulus
Allotropes
Alternate Names
Adiabatic Index
Appearance
Electric Conductivity
Critical Pressure
Critical Temperature
Curie Point
Electrical
Hardness
Magnetic Susceptibility
Magnetic
Neel Point
Neutron Cross Section
Neutron Mass Absorption
Gas Phase
Quantum Numbers
Refractive Index
Space Group
Speed of Sound
Superconducting Point
Thermal Expansion
Valence Electrons
Classification
CategoryOther nonmetals, Nonmetals
CAS GroupVIB
IUPAC GroupVIA
Glawe Number97
Mendeleev Number99
Pettifor Number101
Geochemical Classmajor
Goldschmidt Classlitophile
Radioactivity
RadioactiveNo
Decay Mode
Half-Life
Lifetime
Abundance
Abundance in Earth's crust
461,000 mg/kg
Abundance in Oceans
857,000 mg/L
Abundance in Human Body
Abundance in Meteor
Abundance in Sun
Abundance in Universe1%

Isotopes of Oxygen

Stable Isotopes
16O 17O 18O
Unstable Isotopes
12O 13O 14O 15O 19O 20O 21O 22O 23O 24O 25O 26O 27O 28O

History

Carl Wilhelm Scheele obtained oxygen by heating mercuric oxide and nitrates in 1771, but did not publish his findings until 1777. Joseph Priestley also prepared this new air by 1774. The name oxygen was coined in 1777 by Antoine Lavoisier, whose experiments with oxygen helped to discredit the then-popular phlogiston theory of combustion and corrosion. From the Greek word oxys, acid, and genes, forming

DiscoverersJoseph Priestly, Carl Wilhelm Scheele
Discovery LocationEngland/Sweden
Discovery Year1774
Name OriginGreek: oxys and genes, (acid former).
Oxygen gas can be toxic at elevated partial pressures, leading to convulsions and other health problems
Green and red colors in the Aurora Borealis are caused by oxygen atoms

Uses

Pure oxygen is frequently used to help breathing in patients with respiratory ailments. Oxygen is used in oxyacetylene welding, as an oxidant for rocket fuel, and in methanol and ethylene oxide production. It is also used in the production of steel, plastics and textiles. Plants and animals rely on oxygen for respiration. Used in steel making, welding, and supporting life. Naturally occuring ozone (O3) in the upper atmosphere shields the earth from ultraviolet radiation.

Sources

Obtained primarily from liquid air by fractional distillation. Small amounts are made in the laboratory by electrolysis of water or heating potassium chlorate (KClO3) with manganese dioxide (MnO2) catalyst.