francium

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francium

 (Fr) [fran´se-um]
a chemical element, atomic number 87, atomic weight 223. (See Appendix 6.)

fran·ci·um (Fr),

(fran'sē-ŭm),
Radioactive element of the alkali metal series; atomic no. 87; half-life of most stable known isotope, 223Fr, is 21.8 min.
[France, native country of Marguerite Perey (1909-1975), the discoverer]

francium

A highly radioactive alkali metal (atomic number 87) that decays into astatine, radium and radon. Francium has no commercial utility due to its instability and rarity.

fran·ci·um

(Fr) (fran'sē-ŭm)
Radioactive element of the alkali metal series; atomic no. 87; half-life of most stable known isotope, 223Fr, is 21.8 minutes.
[France, native country of Marguerite Perey (1909-1975), the discoverer]
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