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Element 40 - Zirconium (Zr) sound

From zircon, the name of the semiprecious gem stone in which it was discovered in 1789. A metal unaffected by neutrons, zirconium serves as the inner lining of reactors in nuclear submarines and atomic power plants. It is also used as a building material for jets and rockets.

Properties

Atomic Number: 40
Atomic Weight: 91.224
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d25s2
Oxidation States (Bold most stable): +4
Boiling Point (K): 4682
Melting Point (K): 2128
Density (at 300K -- g/cm3): 6.51
Atomic Volume (at 300K -- cm3/mol) 14.10
Number of stable isotopes: 5
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 93 -- 1.5 x 104 years -- beta particle (electron) emission
95 -- 64 days -- beta particle (electron) emission
Covalent Radius (Å): 1.45
Atomic Radius (Å): 1.60
First Ionization Potential (V): 6.84
Electronegativity (Pauling's): 1.33
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.278
Heat of Vaporization (kJ/mol): 590.5
Heat of Fusion (kJ/mol): 21
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 2.3
Thermal Conductivity (at 300K -- W m-1 K-1): 22.7
Crystal Structure: Hexagonal
Acid-Base Properties: Amphoteric