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• n  a radioactive element of the alkali-metal group discovered as a disintegration product of actinium

• In 1939 she isolated francium, the 87th element in the periodic table.

• Fr
• atomic number 87

News & Articles

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• Laser-Cooled Atoms: Francium [Uncertain Principles]
  Element: Francium (Fr) Atomic Number: 87 Mass: Numerous isotopes ranging in mass from 199 amu to 232 amu, none of them stable. The only ones laser cooled are the five between 208 amu and 212 amu, plus the one at 221 amu. Laser cooling wavelength: 718 nm Doppler cooling limit: 182 ?K. Chemical classification: Alkali…
  Aug. 30, 2013 - ScienceBlogs