Iron (symbol Fe, atomic number 26) is the most-used metal on Earth, the core of steel and of our own blood. It is classified as a transition metal and sits in group 8, period 4 of the periodic table.
Overview
Iron is the chemical element with atomic number 26 and the symbol Fe. With a standard atomic weight of 55.845, it is a transition metal. In the periodic table it occupies group 8 and period 4, and under standard conditions it is normally a solid. Iron is the most-used metal on Earth, the core of steel and of our own blood.
Atomic structure
An atom of Iron has 26 protons in its nucleus and, when neutral, 26 electrons arranged in the configuration [Ar] 3d6 4s2. Its standard atomic weight of 55.845 reflects the natural mix of its stable isotopes.
Discovery and place in the table
Iron has been known since antiquity. It follows Manganese (Mn) and precedes Cobalt (Co) in order of atomic number.
| Atomic number | 26 |
|---|---|
| Symbol | Fe |
| Atomic mass | 55.845 |
| Category | Transition metal |
| Group | 8 |
| Period | 4 |
| Electron configuration | [Ar] 3d6 4s2 |
| Phase at STP | Solid |
| Discovered | Antiquity |