Iron

Source of the photo
x
Author of the description
Gruiz Katalin

Atomic number                                      

26

Atomic mass

55.85 g.mol -1

Electronegativity

1.8

Density

7.8 g.cm-3 at 20°C

Melting point

1536 °C

Boiling point

2861 °C

Vanderwaalsradius

0.126 nm

Ionic radius

0.076 nm (+2) ; 0.064 nm (+3)

Isotopes

8

Electronic shell

[ Ar ] 3d6 4s2

Energy of first ionisation

761 kJ.mol -1

Energy of second ionisation

1556.5 kJ.mol -1

Energy of third ionisation

2951 kJ.mol -1

Standard potential

- o.44 V (Fe2+/ Fe ) ; 0.77 V ( Fe3+/ Fe2+ )

Discovered by

The ancients

 

Iron is a lustrous, ductile, malleable, silver-gray metal (group VIII of the periodic table). It is known to exist in four distinct crystalline forms. Iron rusts in dump air, but not in dry air. It dissolves readily in dilute acids. Iron is chemically active and forms two major series of chemical compounds, the bivalent iron (II), or ferrous, compounds and the trivalent iron (III), or ferric, compounds.

Applications

Iron is the most used of all the metals, including 95 % of all the metal tonnage produced worldwide. Thanks to the combination of low cost and high strength it is indispensable. Its applications go from food containers to family cars, from scredrivers to washing machines, from cargo ships to paper staples.
Steel is the best known alloy of iron, and some of the forms that iron takes include: pig iron, cast iron, carbon steel, wrought iron, alloy steels, iron oxides.