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Element 86 - Radon (Rn) sound

From radium; discovered 1900. Heaviest gaseous element, it is emitted by radium and is itself radioactive; it decays into radioactive polonium and alpha rays. This radiation makes radon useful in cancer therapy; gold needles filled with the gas are implanted into the diseased tissue.

Properties

Atomic Number: 86
Atomic Weight: (222)
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p6
Oxidation States (Bold most stable): 0, +2
Boiling Point (K): 211.4
Melting Point (K): 202
Density (at STP -- g/l): 9.73
Atomic Volume (liquid state at boiling point -- cm3/mol) 50.5
Number of natural radioactive isotopes: 3
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 222 -- 3.824 days -- alpha particle emission
Atomic Radius (Å): 1.34
First Ionization Potential (V): 10.748
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.094
Heat of Vaporization (kJ/mol): 16.40
Heat of Fusion (kJ/mol): 2.9
Thermal Conductivity (at 300K -- W m-1 K-1): 0.00364
Crystal Structure: Cubic, face centered