Atomic Properties
- Atomic Number
- 8
- Atomic Mass
- 15.9990 u
- Electron Configuration
- [He] 2s2 2p4
- Electronegativity
- 3.44
- Block
- p-block
- Group
- 16
- Period
- 2
Physical Properties
- Phase (STP)
- gas
- Melting Point
- 54.36 K
- Boiling Point
- 90.19 K
- Density
- 0.0014 g/cm³
About Oxygen
Essential for respiration; most abundant element in Earth's crust.
Isotopes of Oxygen
Oxygen has 3 naturally occurring isotopes.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 16O | 16 | 15.99491462 | 99.76% | Stable |
| 17O | 17 | 16.99913176 | 0.0380% | Stable |
| 18O | 18 | 17.99915961 | 0.2050% | Stable |
Data source: NIH PubChem (aggregated from IUPAC, NIST)