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Name: Uranium Symbol: U
Group: Rare Earth, Actinides Atomic weight: 238.029
Density @ 293 K: 18.9 g/cm3 Atomic volume: 12.59 cm3/mol
Group: Rare Earth, Actinides discovered: 1789


state (s, l, g): s
melting point: 1405.2 K boiling point: 4203 K
Heat of fusion: 8.520 kJ/mol Heat of vaporization: 477.0 kJ/mol


1st ionization energy: 584 kJ/mole
electronegativity: 1.7 2nd ionization energy: kJ/mole
electron affinity: kJ/mole 3rd ionization energy: kJ/mole
Specific heat: 0.12 J/gK heat atomization: 490 kJ/mole atoms

Oxidation & Electrons:

Shells: 2,8,18,32,21,9,2 electron configuration: [Rn] 5f3 6d1 7s2
minimum oxidation number: 0 maximum oxidation number: 6
min. common oxidation no.: 0 max. common oxidation no.: 6

Appearance & Characteristics:

structure: hcp:hex cls pkd distorted color: silvery
uses: nuclear reactor fuel toxicity:
hardness: mohs characteristics: Radioactive


reaction with air: mild, =>U3O8
reaction with 6M HCl: mild, =>H2 reaction with 6M HCl: mild, =>H2
reaction with 15M HNO3: passivated reaction with 6M NaOH: none

Other Forms:

number of isotopes: 3 hydride(s): UH3
oxide(s): UO UO2 U2O5 U3O8 UO3 chloride(s): UCl3 UCl4 UCl5 UCl6


ionic radius (2- ion): pm ionic radius (1- ion): pm
atomic radius: 156 pm ionic radius (1+ ion): pm
ionic radius (2+ ion): pm ionic radius (3+ ion): 116.5 pm


thermal conductivity: 27.5 J/m-sec-deg
electrical conductivity: 33.333 1/mohm-cm polarizability: 27.4 A^3


source: Uranite (oxide)
rel. abund. solar system: -2.046 log abundance earth's crust: 0.4 log
cost, pure: $/100g cost, bulk: $/100g