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

/fran·ci·um/ (Fr) (fran´se-um) a chemical element, at. no. 87.

francium (Fr)

[fran′sē·əm]
Etymology: France
a metallic element of the alkali metal group. Its atomic number is 87, and the mass of its longest-lived isotope is 223. Formed from the decay of actinium, all of its 20 isotopes are radioactive and short-lived.

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]

francium

a chemical element, atomic number 87, atomic weight 223, symbol Fr. See Table 6.