General | States | Energies | Oxidation & Electrons |Appearance & Characteristics
Reactions | Other Forms |Radius | Conductivity | Abundance
Encyclopedia Britannica articles


Name Iron Symbol Fe
atomic number 26 Atomic weight 55.847
Density @ 293 K 7.86 g/cm3 Atomic volume 7.1 cm3/mol
Group Trans. Met. discovered 0


state (s, l, g) s
melting point 1808.2 K boiling point 3023 K
Heat of fusion 13.80 kJ/mol Heat of vaporization 349.60 kJ/mol
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1st ionization energy 759.3 kJ/mole electronegativity 1.9
2nd ionization energy 1561.1 kJ/mole electron affinity 15.7 kJ/mole
3rd ionization energy 2957.3 kJ/mole Specific heat 0.44 J/gK
heat atomization 418 kJ/mole atoms

Oxidation & Electrons

Shells 2,8,14,2 electron configuration [Ar] 3d6 4s2
minimum oxidation number -2 maximum oxidation number 6
min. common oxidation no. 0 max. common oxidation no. 3
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Appearance & Characteristics

structure bcc: body-centered cubic color gray
uses steel toxicity
hardness 4.5 mohs characteristics fairly soft when pure


reaction with air mild, = Fe3O4 reaction with 6M HCl mild, = H2, FeCl2
reaction with 6M HCl mild, = H2, FeCl2 reaction with 15M HNO3 passivated
reaction with 6M NaOH
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Other Forms

number of isotopes 4 hydride(s) none
oxide(s) FeO Fe3O4 Fe2O3 chloride(s) FeCl2 FeCl3


ionic radius (2- ion) pm ionic radius (1- ion) pm
atomic radius 126 pm ionic radius (1+ ion) pm
ionic radius (2+ ion) 83.5 pm ionic radius (3+ ion) 73.8 pm
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thermal conductivity 72.8 J/m-sec-deg electrical conductivity 102.987 1/mohm-cm
polarizability 8.4 A^3


source Hematite,magnetite(oxide) rel. abund. solar system 5.954 log
abundance earth's crust 4.8 log cost, pure 6.7 $/100g
cost, bulk 0.021 $/100g
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World Wide Web presentation of Chemicool Periodic Table is © Copyright 1996-99 by David D. Hsu. Some data were provided by and used with the permission of JCE Software and is owned and copyright by the Division of Chemical Education, Inc. Additional data were provided by Perkin-Elmer through Peter Lykos of IIT. The information may not be redistributed without the permission of David Hsu or JCE Software.