8 - Oxygen diatomic nonmetal

Discovered by Carl Scheele in 1774

  • Atomic Radius (Å)
  • Cividis
Oxygen

Oxygen is a chemical element with symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table and is a highly reactive nonmetal and oxidizing agent that readily forms compounds (notably oxides) with most elements. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium.

H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
57-71 La-Lu Lanthanides
89-103 Ac-Lr Actinides
 Shell Electrons Orbitals
122 in 1s
262 in 2s + 4 in 2p
OxygenOElectron 1Electron 2Electron 1Electron 2Electron 3Electron 4Electron 5Electron 6
16  u Atomic Mass
0.6  Å Atomic Radius
90.2  K Boiling Point
16 Group
-2 Common Oxidation States
0.66  Å Covalent Radius
0.00143  g/cm³ Density
141  kJ/mol Electron Affinity
1s2 2s2 2p4 Electron Configuration
[He] 2s2 2p4 Electron Configuration (semantic)
3.44 Electronegativity
8 Electrons
13.6  eV First Ionization Energy
-2 ICSD Oxidation States
1313.9, 3388.3, 5300.5, 7469.2, 10989.5, 13326.5, 71330, 84078  kJ/mol Ionization Energies
50.5  K Melting Point
101 Mendeleev Number
2 Number of Shells
6 Electron Valency
8 Neutrons
8 Atomic Number
8 Number of Isotopes
-2, -1, 1, 2 Oxidation States
2 Period
Gas Phase
8 Protons
2, 6 Electron Shell Occupations
0.918  J/(g K) Specific Heat