Atomic Properties
- Atomic Number
- 26
- Atomic Mass
- 55.8450 u
- Electron Configuration
- [Ar] 3d6 4s2
- Electronegativity
- 1.83
- Block
- d-block
- Group
- 8
- Period
- 4
Physical Properties
- Phase (STP)
- solid
- Melting Point
- 1811.00 K
- Boiling Point
- 3134.00 K
- Density
- 7.8740 g/cm³
About Iron
Most used metal; essential for hemoglobin; Earth's core is mostly iron.
Why "Fe" for Iron?
Fe←Ferrum(Latin)
The symbol Fe comes from "Ferrum," the Latin word for iron. The English name "Iron" derives from the Old English "īsern" and Proto-Germanic origins, possibly related to early Celtic words.
Isotopes of Iron
Iron has 4 naturally occurring isotopes.
| Isotope | Mass Number | Atomic Mass (u) | Abundance | Type |
|---|---|---|---|---|
| 54Fe | 54 | 53.93960899 | 5.845% | Stable |
| 56Fe | 56 | 55.93493633 | 91.75% | Stable |
| 57Fe | 57 | 56.93539284 | 2.119% | Stable |
| 58Fe | 58 | 57.93327443 | 0.2820% | Stable |
Data source: NIH PubChem (aggregated from IUPAC, NIST)