◄ Ac   Pb ▲   ▼ Pu   Pa ►

Thorium ∙ thorium ∙ torio ∙ torio
group IV: RH₄, RO₂

• melting point: 1750°C
• boiling point: 4000°C
• density: 11.7 g/cm³

☢ radioisotopes: Th-234 (T1/2=24 d) NORM