ASCII PERIODIC TABLE OF THE ELEMENTS
Fr
Relative atomic mass: [223]
English: Francium
French: Francium
Croatian: Francij
German: Francium
Italian: Francio
Spanish: Francio
Atomic number: 87
Group numbers: 1
Period: 7
Standard state (20 °C): solid
Discovery: 1939 Marguerite Perey (FR)
Francium was discovered by Marguerite Perey (FR) in 1939. Named for 'France', the nation of its discovery. It is a highly rare and unstable, radioactive metal. Its chemical properties are similar to caesium. Francium is formed from the decay of actinium. It can be produced by bombarding radium or astatine with neutrons. Since its isotopes have such short half-lives there are no commercially significant compounds of francium.
Electronic configuration: [Rn] 7s1
Formal oxidation number: +1
Atomic radius: 282 pm
Electronegativities: 0.7
Thermal conductivity: 15 W/(m K)
Electrical resistivity (20 °C): - μΩcm
Melting point: 27 °C
Boiling point: 677 °C
Heat of fusion: - kJ/mol
Heat of vaporization: - kJ/mol
Heat of atomization: 75 kJ/mol
86Rn <= 87Fr => 88Ra
ASCII Periodic Table of the Elements
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31 Mar. 2008
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