Iron 26

Atomic No. Order:

Alphabetic Order:

Periodic Table

2, 8,

14, 2

Fe
26

Ru
44

Os
76

Hs
108

Upo
158

Bno
208

Iron

Symbol

Atomic Number

Relative Atomic Mass
¹²C = 12.0000

55.845 (±2) [Since 1993]

Atomic Radius pm

124

First Ionisation Energy
kJ mol ^-1

759.3

Ionisation Energy (eV)

7.9024

Electronegativity

1.83

Density kg m ^-3

7874 [293 K]
7035 [m.p.]

Molar Volume cm ³

7.09

Thermal Conductivity
W m ^-1 K ^-1

80.2 [300 K]

Melting Point K

1808

Boiling Point K

3023

Number of Isotopes

Isotope Atomic mass/u Mole fraction

54Fe 53.939 6147(14) 0.058 45(35)
56Fe 55.934 9418(15) 0.917 54(36)
57Fe 56.935 3983(15) 0.021 19(10)
58Fe 57.933 2801(15) 0.002 82(4)

Inner + outer Shells

Inner + outer Orbitals

Filling Orbital

3d ⁶

Ground State Electron
Configuration

[Ar]

3d ⁶

4s ²

Ground State Electron
Configuration with
free Orbitals (n= 10)

0, 0, 4, 6

Ground State Electron
Configuration with
compressed Orbitals (n= 24)

0, 0, 0, 24

Singularity

	s	p	d		f	g	h	i	j
1	2
2	2	6
3	2	6	6	4
4	2	6	10		14
5
6
7

Term Symbol

⁵D ₄

Discovery

The element has been known from prehistoric times.

Name Derived From

The name derives from the Anglo-Saxon iron of unknown origin. The chemical symbol [Fe] is derived from the Latin ferrum for "firmness." It is of interest to note that 56Fe has a larger mass defect than any other nuclide. It is, therefore, the ultimate endproduct of stellar nuclear fusion.

APSIDIUM ©	Created:	2002- 06-01	026.pdf
	Page update:	2004-12-08	026.pdf