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Element 31 - Gallium (Ga) sound

From Gallia, the old name for France; discovered 1875. A metal that melts in the hand, it is one of the few that expands as it freezes, as do nonmetals and most gases. Its high boiling point (2478 K) makes it ideal for recording temperatures that would vaporize a thermometer.

Properties

Atomic Number: 31
Atomic Weight: 69.723
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p1
Oxidation States (Bold most stable): +3
Boiling Point (K): 2478
Melting Point (K): 302.92
Density (at 300K -- g/cm3): 5.91
Atomic Volume (at 300K -- cm3/mol) 11.80
Number of stable isotopes: 2
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 67 -- 78.2 hours -- orbital electron capture
72 -- 14.10 hours -- beta particle (electron) emission
Covalent Radius (Å): 1.26
Atomic Radius (Å): 1.41
First Ionization Potential (V): 5.999
Electronegativity (Pauling's): 1.81
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.371
Heat of Vaporization (kJ/mol): 256.06
Heat of Fusion (kJ/mol): 5.59
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 1.8
Thermal Conductivity (at 300K -- W m-1 K-1): 40.6
Crystal Structure: Orthorhombic
Acid-Base Properties: Amphoteric