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Element 43 - Technetium (Tc) sound

From technetos, or artificial; produced 1937. the first man-made element, it was originally produced by the atomic bombardment of molybdenum. Later it was found among the fission products of uranium.

Properties

Atomic Number: 43
Atomic Weight: (98) most stable/best known isotope
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d55s2
Oxidation States (Bold most stable): +4, +6, +7
Boiling Point (K): 4538
Melting Point (K): 2477
Density (at 300K -- g/cm3): 11.5
Atomic Volume (at 300K -- cm3/mol) 8.5
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 97 -- 2.6 x 106 years -- orbital electron capture
98 -- 4.2 x 106 years -- beta particle (electron) emission
99 -- 2.13 x 105 years -- beta particle (electron) emission
Covalent Radius (Å): 1.27
Atomic Radius (Å): 1.36
First Ionization Potential (V): 7.28
Electronegativity (Pauling's): 1.9
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.24
Heat of Vaporization (kJ/mol): 502.0
Heat of Fusion (kJ/mol): 23
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 0.001
Thermal Conductivity (at 300K -- W m-1 K-1): 50.6
Crystal Structure: Hexagonal
Acid-Base Properties: Very acidic