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Francium
Symbol: Fr
Atomic Number: 87
Atomic Weight: 223.0197
Element Classification: Alkali Metal
Discovered By: Marguerite Derey
Discovery Date: 1939 (France)
Name Origin: Named for France, the nation of its discovery.
Density (g/cc): n/a
Melting Point (°K): 300
Boiling Point (°K): 950
Appearance: n/a
Atomic Radius (pm): n/a
Atomic Volume (cc/mol): n/a
Covalent Radius (pm): n/a
Ionic Radius: 180 (+1e)
Specific Heat (@20°C J/g mol): n/a
Fusion Heat (kJ/mol): 15
Evaporation Heat (kJ/mol): n/a
Thermal Conductivity (@25°C W/m K):
Debye Temperature (°K): n/a
Pauling Negativity Number: 0.7
First Ionizing Energy (kJ/mol): ~375
Oxidation States: 2
Electronic Configuration: [Rn] 7s1
Lattice Structure: Body-Centered Cubic (BCC)
Lattice Constant (Å): n/a
Lattice C/A Ratio: n/a