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92
U
238.03

Uranium

Actinides · Group 6 · Period 6–7 (f)

Atomic properties

Atomic number92
SymbolU
Standard atomic weight238.03
ClassificationActinides
Groupf-block series
Period7
Blockf-block (actinide)
Electron configuration[Rn] 5f3 6d1 7s2
Electronegativity (Pauling)1.38
Common oxidation states+6, +4

Physical properties

Phase at 20 °CSolid
Density19.1 g/cm³
Melting point1132.2 °C
Boiling point4131 °C
Discovered1789
CAS number