The Element Francium
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Atomic Number: 87
Atomic Weight: 223
Melting Point: 300 K (27°C or 81°F)
Boiling Point: Unknown
Phase at Room Temperature: Solid
Element Classification: Metal
Period Number: 7 Group Number: 1 Group Name: Alkali Metal
What's in a name? Named for the country of France.
Say what? Francium is pronounced as FRAN-see-em.
History and Uses:
Francium was discovered by Marguerite Catherine Perey, a French chemist, in 1939 while analyzing actinium's decay sequence. Although considered a natural element, scientists estimate that there is no more than one ounce of francium in the earth's crust at one time. Since there is so little naturally occurring francium on earth, scientists must produce francium in order to study it. Francium can be produced by bombarding thorium with protons or by bombarding radium with neutrons.
Francium's most stable isotope, francium-223, has a half-life of about 22 minutes. It decays into radium-223 through beta decay or into astatine-219 through alpha decay.
Due to the small amounts produced and its short half-life, there are currently no uses for francium outside of basic scientific research.
Estimated Crustal Abundance: Not Applicable
Estimated Oceanic Abundance: Not Applicable
Number of Stable Isotopes: 0 (View all isotope data)
Ionization Energy: 3.9 eV
Oxidation States: +1
3s2 3p6 3d10
4s2 4p6 4d10 4f14
5s2 5p6 5d10