26Fe55.845
Iron (Fe)
Element 26 Ā· Transition metal
Iron (Fe) is a chemical element with atomic number 26. It is classified as a transition metal in period 4, group 8 of the periodic table (the d-block). Its standard atomic weight is 55.845 u and its ground-state electron configuration is [Ar] 3dā¶ 4sĀ².
Iron facts
| Atomic number (Z) | 26 |
|---|---|
| Symbol | Fe |
| Standard atomic weight | 55.845 u |
| Category | Transition metal |
| Group | 8 |
| Period | 4 |
| Block | d-block |
| Electron configuration | [Ar] 3dā¶ 4sĀ² |
| Electronegativity (Pauling) | 1.83 |
| State at 20 Ā°C | Solid |
| Protons / electrons | 26 / 26 |
| Neutrons (most common isotope, approx.) | 30 |
| Molar mass | 55.845 g/mol |