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Element 53 - Iodine (I) sound

From iodes, or violet; discovered 1811; a blue-black solid which turns into a violet vapor when heated. Formerly prepared from seaweed, it is now produced from oil-well brines. Most table salt is now "iodized" to supplement the human diet; an iodine deficiency causes thyroid trouble.

Properties

Atomic Number: 53
Atomic Weight: 126.9045
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d105s25p5
Oxidation States (Bold most stable): -1, +1, +5, +7
Boiling Point (K): 457.5
Melting Point (K): 386.7
Density (at 300K -- g/cm3): 4.93
Atomic Volume (at 300K -- cm3/mol) 25.70
Number of stable isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 129 -- 1.6 x 107 years -- beta particle (electron) emission
131 -- 8.040 days -- beta particle (electron) emission
Covalent Radius (Å): 1.33
Atomic Radius (Å): 1.32
First Ionization Potential (V): 10.451
Electronegativity (Pauling's): 2.66
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.145
Heat of Vaporization (kJ/mol): 20.9
Heat of Fusion (kJ/mol): 7.76
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 10-11
Thermal Conductivity (at 300K -- W m-1 K-1): 0.449
Crystal Structure: Orthorhombic
Acid-Base Properties: Very acidic