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Element 9 - Fluorine sound

From fluo, or flow; discovered 1771. Fluorine is the most reactive of the non-metals; only a few of the inert gases resist it. It corrodes platinum, a material that withstands most other chemicals. In a stream of fluorine gas, wood and rubber burst into flame--and even asbestos glows.

Properties

Atomic Number: 9
Atomic Weight: 18.99840
Electron Configuration (at ground state): 1s22s22p5
Oxidation States (Bold most stable): -1
Boiling Point (K): 85.0
Melting Point (K): 53.55
Density (at STP -- g/l): 1.696
Atomic Volume (liquid state at boiling point -- cm3/mol) 17.10
Number of stable isotopes: 1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type: 18 -- 109.8 min -- positron emission
Covalent Radius (Å): 0.72
Atomic Radius (Å): 0.57
First Ionization Potential (V): 17.422
Electronegativity (Pauling's): 3.98
Specific Heat Capacity (at 300K -- J g-1 K-1): 0.824
Heat of Vaporization (kJ/mol): 3.2698
Heat of Fusion (kJ/mol): 0.26
Thermal Conductivity (at 300K -- W m-1 K-1): 0.0279
Crystal Structure: Cubic