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francium
(Encyclopedia)francium frănˈsēəm [key] [from France], radioactive chemical element; symbol Fr; at. no. 87; mass no. of most stable isotope 223; m.p. about 27℃ (estimated); b.p. 677℃ (estimated); sp. gr. unk...virginium
(Encyclopedia)virginium: see francium.Fr
(Encyclopedia)Fr, symbol for the element francium. ...Periodic Table of the Elements: Francium
(Encyclopedia)Periodic Table of the Elements: Francium ...alkali metals
(Encyclopedia)alkali metals, metals found in Group 1 of the periodic table. Compared to other metals they are soft and have low melting points and densities. Alkali metals are powerful reducing agents and form univ...synthetic elements
(Encyclopedia)synthetic elements, in chemistry, radioactive elements that were not discovered occurring in nature but as artificially produced isotopes. They are technetium (at. no. 43), which was the first element...Elements (table)
(Encyclopedia)Elements 1 Parentheses indicate most stable isotope; brackets enclose lower and upper bounds of weight variation. ...Browse by Subject
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