Atomic Properties
- Atomic Number
- 18
- Atomic Mass
- 39.9480 u
- Electron Configuration
- [Ne] 3s2 3p6
- Electronegativity
- —
- Block
- p-block
- Group
- 18
- Period
- 3
Physical Properties
- Phase (STP)
- gas
- Melting Point
- 83.81 K
- Boiling Point
- 87.30 K
- Density
- 0.0018 g/cm³
About Argon
Third most abundant gas in atmosphere; used in welding and light bulbs.
Isotopes of Argon
Argon has 3 naturally occurring isotopes.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 36Ar | 36 | 35.9675451 | 0.3336% | Stable |
| 38Ar | 38 | 37.96273211 | 0.0629% | Stable |
| 40Ar | 40 | 39.96238312 | 99.60% | Stable |
Data source: NIH PubChem (aggregated from IUPAC, NIST)