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Element 78 - Platinum (Pt) sound

From platina, or little silver; discovered 16th century. found in nuggets of up to 21 pounds, it is used not only in weights and measures but also in catalysts, delicate instruments, and electrical equipment. Its cost (more than gold) has demanded a hallmark for platinum jewelery

Properties

Atomic Number: 78
Atomic Weight: 195.08
Electron Configuration (at ground state): 1s22s22p63s23p63d104s24p64d104f145s25p65d96s1
Oxidation States (Bold most stable): +2, +4
Boiling Point (K): 4100
Melting Point (K): 2042.1
Density (at 300K -- g/cm3): 21.45
Atomic Volume (at 300K -- cm3/mol) 9.10
Number of stable isotopes: 4
Number of natural radioactive isotopes: 2
Covalent Radius (Å): 1.30
Atomic Radius (Å): 1.39
First Ionization Potential (V): 9.0
Electronegativity (Pauling's): 2.28
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.13
Heat of Vaporization (kJ/mol): 510.45
Heat of Fusion (kJ/mol): 19.66
Electrical Conductivity (at 293K for polycrystalline material -- 106 (ohms)-1 cm-1): 9.4
Thermal Conductivity (at 300K -- W m-1 K-1): 71.6
Crystal Structure: Cubic, face centered
Acid-Base Properties: Very basic