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Pronunciation: fran'se-um

Definition: 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]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.