fermium

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fermium

 (Fm) [fer´me-um]
a chemical element, atomic number 100, atomic weight 253. (See Appendix 6.)

fer·mi·um (Fm),

(fĕr'mē-ŭm),
Radioactive element, artificially prepared in 1955, atomic no. 100, atomic wt. 257.095; 257Fm has the longest known half-life (100.5 days) of this transuranium element.
[Enrico Fermi]

fer·mi·um

(Fm) (fer'mē-ŭm)
Radioactive element, artificially prepared in 1955; atomic no. 100, atomic wt. 257.095; 257Fm has the longest known half-life (100.5 days).
[Enrico Fermi]
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