Iron

Iron Element Properties

d25
Mn
Manganese
d26
Fe
Iron
d27
Co
Cobalt
General
NameIron
SymbolFe
Number26
Group Number8
GroupTransition metals
Blockd
Density7.86 g/cm3
Atomic Weight55.847 g/mol
Atomic Volume7.1 cm3/mol
DiscoverNone


States
StateSolid
Melting Point1811 K
Boiling Point3134 K
Triple PointNil
Critical PointNil
Heat of Fusion13.81 kJ/mol
Heat of Vaporization340 kJ/mol


Energies
First Ionization Energy759.3 kJ/mole
Second Ionization Energy1561.1 kJ/mole
Third Ionization Energy2957.3 kJ/mole
Electronegativity1.9
Electron Affinity15.7 kJ/mole
Specific Heat0.44 J/gK
Heat Atomization418 kJ/mole atoms


Oxidation and Electrons
Shells2,8,14,2
Electron Configuration[Ar] 3d6 4s2
Minimum Oxidation Number-2
Maximum Oxidation Number6
Minimum Common Oxidation Number0
Maximum Common Oxidation Number3


Appearance and Characteristics
Crystal Structurebody-centered cubic
Characteristicsfairly soft when pure
Colorgray
Usessteel
Hardness4.5 mohs
ToxicityNone


Reactions
Reaction with Airmild, =>Fe3O4
Reaction with 6M HClmild, =>H2, FeCl2
Reaction with 15M HNO3passivated
Reaction with 6M NaOHNone


Other Forms
Number of Isotopes4
HydrideNone
OxideFeO Fe3O4 Fe2O3
ChlorideFeCl2 FeCl3


Radius
Atomic Radius126 pm
Ionic Radius (1+ ion)Nil
Ionic Radius (1- ion)Nil
Ionic Radius (2+ ion)83.5 pm
Ionic Radius (2- ion)Nil
Ionic Radius (3+ ion)73.8 pm


Conductivity
Thermal Conductivity72.8 J/m-sec-deg
Electrical Conductivity102.987 1/mohm-cm
Polarizability8.4 A3


Abundance
SourceHematite,magnetite(oxide)
Relation Abundance Solar System5.954 log
Abundance Earth's Crust4.8 log


d25
Mn
Manganese
d26
Fe
Iron
d27
Co
Cobalt