Technical data for Thorium

Overview
NameThorium
SymbolTh
Atomic Number90
Atomic Weight232.0381
Density11.724 g/cm3
Melting Point1750 °C
Boiling Point4820 °C

Thermal properties
PhaseSolid
Melting Point1750 °C
Boiling Point4820 °C
Absolute Melting Point2023 K
Absolute Boiling Point5093 K
Heat of Fusion16 kJ/mol
Heat of Vaporization530 kJ/mol
Heat of CombustionN/A
Specific Heat118 J/(kg K)[note]
Thermal Conductivity54 W/(m K)
Thermal Expansion0.000011 K-1

Bulk physical properties
Density11.724 g/cm3
Density (Liquid)N/A
Molar Volume0.0000197917
Brinell Hardness400 MPa
Mohs Hardness3 MPa
Vickers Hardness350 MPa
Bulk Modulus54 GPa
Shear Modulus31 GPa
Young Modulus79 GPa
Poisson Ratio0.27
Speed of Sound2490 m/s
Thermal Conductivity54 W/(m K)
Thermal Expansion0.000011 K-1

Reactivity
Valence4
Electronegativity1.3
ElectronAffinityN/A
Ionization Energies
587, 1110, 1930, 2780 kJ/mol

Health and Safety
Autoignition Point130 °C
FlashpointN/A

Classifications
Alternate NamesNone
Nams of AllotropesNone
Blockf
GroupN/A
Period7
Electron Configuration[Rn]6d27s2
ColorSilver
Discovery
1829 in Sweden
Gas phaseN/A
CAS NumberCAS7440-29-1

Electrical properties
Electrical TypeConductor
Electrical Conductivity6.7×106 S/m
Resistivity1.5×10-7 m Ω
Superconducting Point1.38

Magnetic properties
Magnetic TypeN/A
Curie PointN/A
Mass Magnetic Susceptibility5.3×10-9
Molar Magnetic Susceptibility1.23×10-9
Volume Magnetic Susceptibility0.0000621

Abundances
% in Universe4×10-8%
% in Sun3×10-8%
% in Meteorites3.9×10-6%
% in Earth's Crust0.0006%
% in Oceans4×10-12%
% in HumansNone

Atomic dimensions and structure
Atomic RadiusN/A
Covalent RadiusN/A
Van der Waals RadiusN/A
Crystal StructureFace Centered Cubic
Lattice Angles
π/2, π/2, π/2
Lattice Constants
508.42, 508.42, 508.42 pm
Space Group NameFm_ 3m
Space Group Number225

Nuclear Properties
Half-Life1.406×1010 y
Lifetime2.0285×1010 y
Stable Isotopes
232Th
Isotopic Abundances
232Th100%

Notes on the properties of Thorium:
Specific Heat: Value given for solid phase.