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Element 87 - Francium (Fr)

From France; discovered 1939. A short-lived product of the decay of actinium. It was discovered by Marguerite Perey, a one-time assistant to Marie Curie.

Properties
Atomic Number:	87
Atomic Weight:	(223)
Electron Configuration (at ground state):	1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰6s²6p⁶7s¹
Oxidation States (Bold most stable):	+1
Boiling Point (K):	950
Melting Point (K):	300
Number of natural radioactive isotopes:	1
Mass Number (Bold naturally occurring) -- Half-Life -- Disintigration Type:	212 -- 19.3 minutes -- orbital electron capture, alpha particle emission 222 -- 15 minutes -- beta particle (electron) emission 223 -- 21.8 minutes -- beta particle (electron) emission
Atomic Radius (Å):	2.7
Electronegativity (Pauling's):	0.7
Heat of Vaporization (kJ/mol):	64
Heat of Fusion (kJ/mol):	2.1
Thermal Conductivity (at 300K -- W m^-1 K^-1):	15
Crystal Structure:	Cubic, body centered
Acid-Base Properties:	Very basic