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- Name : Francium
- Symbol : Fr
- Atomic # : 87
- Atom weight: 223 (Most stable isotope)
- Melting P. : 27 (Calculated value)
- Boiling P. : 677 (Calculated value)
- Oxidation : +1
- Pronounced : FRAN-si-em
- From : Named for the nation of discovery, France
- Identified : Marguerite Perey in 1939
- Appearance :
- Note : Highly unstable radioactive element
-
- [Properties]
-
- Francium is the heaviest of the alkali metals in Group 1A on the periodic
- chart. It is also the most scarce of these metals. In fact there is only an
- ounce of natural francium scattered throughout the soil and rock of the
- earth; so no one has bothered to come up with a way to find it, let alone
- refine it. All francium samples that are available for study today are
- manufactured artificially. There are two different approaches to producing
- small quantities of francium. The more direct approach is to bombard thorium
- with protons. The second approach is less direct, but usually more
- practical. Radium is the parent element in this case. Once it is subjected
- to heavy neutron bombardment, it is converted to a species of actinium
- that decays naturally and quickly to thorium. Finally, the thorium decays
- naturally to francium.
-