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26 Fe Iron Iron

Iron (Fe)

Transition Metals · Solid · Period 4 · Group 8

Element Properties

Atomic Number
26
Symbol
Fe
Atomic Mass
55.84
Standard State
Solid
Period
4
Group
8
Electronegativity
1.83
Atomic Radius
194
Ionization Energy
7.9
Electron Affinity
0.16
Oxidation States
+3, +2
Melting Point
1811 K (1537.85 °C)
Boiling Point
3134 K (2860.85 °C)
Density
7.874
Electron Configuration
[Ar]4s2 3d6
Year Discovered
Ancient

Electron shells

Electron shell diagram of Iron (atomic number 26)

[Ar]4s2 3d6

Electrons are arranged in shells (principal energy levels) around the nucleus. The diagram is a schematic — orbitals in the same shell are not drawn separately.

Frequently asked questions

What is the atomic number of Iron?

The atomic number of Iron is 26, which equals the number of protons in its nucleus.

What is the atomic mass of Iron?

The atomic mass of Iron is approximately 55.84 u (one twelfth of the mass of a carbon-12 atom).

What is the electron configuration of Iron?

The electron configuration of Iron is [Ar]4s2 3d6.

Where is Iron in the periodic table?

Iron is located in period 4, group 8.

When was Iron discovered?

Iron has been known since antiquity.

Related elements

Same group

Same period