NO. 090Actinide

Th

Thorium

Thorium is a weakly radioactive actinide with potential use as a nuclear fuel. It is more abundant than uranium and is studied for safer nuclear energy systems.

Crystal Structure

Face-centered cubic

Technical Specifications

Atomic Mass232.04 u

Density11.7 g/cm³

Melting Point2115 K

Boiling Point5061 K

Atomic Radius180 pm

Electronegativity1.3

Ionization Energy587 kJ/mol

Electron Affinity50 kJ/mol

Bonding TypeMetallic

Oxidation States4

Acid/BaseBasic

ReactivityMedium

Electron Configuration

[Rn] 6d2 7s2

Discovered ByJöns Jakob Berzelius

Year1828

Known Isotopes

Th-232