90
Th
232.04
Thorium
Element 90 · 232.04 u · f-block
actinide
A weakly radioactive metal being explored as nuclear fuel. More abundant than uranium and produces less waste.
Phase (STP)
Solid
Melting Point
1750 °C
Boiling Point
4788 °C
Density
11.72 g/cm³
Electronegativity
1.3
Atomic Radius
180 pm
Ionization Energy
587 kJ/mol
Electron Affinity
113 kJ/mol
Discovered
1829 · Jons Jacob Berzelius
Electron Configuration
[Rn] 6d2 7s2
Electron Orbitals
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