8 O
Reactive nonmetal
Oxygen
Required for respiration.
Properties of Oxygen
- Atomic number (Z)
- 8
- Symbol
- O
- Atomic mass
- 15.999 g/mol
- Category
- Reactive nonmetal
- Group
- 16
- Period
- 2
- Electron configuration
- [He] 2s² 2p⁴
- Electronegativity (Pauling)
- 3.44
- Atomic radius
- 48 pm
- First ionization energy
- 1314 kJ/mol
- Melting point
- 54.36 K (-218.8 °C)
- Boiling point
- 90.2 K (-182.9 °C)
- Density
- 0.001429 g/cm³
- Phase at 25 °C
- Gas
- Discovered
- Discovered in 1774
Frequently asked questions
What is Oxygen?
Oxygen (O) is a reactive nonmetal, element number 8 on the periodic table. Required for respiration.
What is the atomic number and atomic mass of Oxygen?
Oxygen has atomic number 8 and an atomic mass of about 15.999 g/mol.
What is the electron configuration of Oxygen?
The electron configuration of Oxygen is [He] 2s² 2p⁴.
Where is Oxygen on the periodic table?
Oxygen sits in group 16, period 2, and is classified as a reactive nonmetal.