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Element 76 - Osmium (Os) sound

From osme, or odor; discovered 1804. A metal with a pungent smell, it is used to produce alloys of extreme hardnes.. Pen tips are 60 percent osmium. It is the densest metal known; a brick-sized chunk of osmium weighs about 56 pounds.

Properties

Atomic Number: 76
Atomic Weight: 190.2
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d104f145s25p65d66s2
Oxidation States (Bold most stable): +2, +3, +4, +6, +8
Boiling Point (K): 5300
Melting Point (K): 3300
Density (at 300K -- g/cm3): 22.6
Atomic Volume (at 300K -- cm3/mol) 8.43
Number of stable isotopes: 7
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 194 -- 6.0 years -- beta particle (electron) emission
Covalent Radius (Å): 1.26
Atomic Radius (Å): 1.35
First Ionization Potential (V): 8.7
Electronegativity (Pauling's): 2.2
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.13
Heat of Vaporization (kJ/mol): 627.6
Heat of Fusion (kJ/mol): 29.29
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 12.3
Thermal Conductivity (at 300K -- W m-1 K-1): 87.6
Crystal Structure: Hexagonal
Acid-Base Properties: Slightly acidic