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Element 90 - Thorium (Th) sound

From Thor, Scandinavian war-god; discovered 1828. Thorium can be used instead of scare uranium as a reactor fuel because it is readily converted into uranium. Almost as abundant as lead, earthly thorium stores much more energy can all uranium, coal, oil, and other fuels combined.

Properties

Atomic Number: 90
Atomic Weight: 232.0381
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p66d27s2
Oxidation States (Bold most stable): +4
Boiling Point (K): 5060#
Melting Point (K): 2028
Density (at 300K -- g/cm3): 11.72
Atomic Volume (at 300K -- cm3/mol) 19.90
Number of natural radioactive isotopes: 6
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 228 -- 1.913 years -- alpha particle emission
230 -- 7.7 x 104 years -- alpha particle emission
232 -- 1.40 x 1010 years -- alpha particle emission
Covalent Radius (Å): 1.65
Atomic Radius (Å): 1.80
First Ionization Potential (V): 6.08
Electronegativity (Pauling's): 1.3
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.113
Heat of Vaporization (kJ/mol): 543.92
Heat of Fusion (kJ/mol): 15.65
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 7.1
Thermal Conductivity (at 300K -- W m-1 K-1): 54
Crystal Structure: Cubic, face centered
Acid-Base Properties: Slightly basic