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#87 Francium - rarity BROWNIAN-MANIACS
1st ionization energy 3.9 eV 0.85%
appearance - 15.25%
atomic mass 223 u 0.85%
atomic number 87 0.85%
atomic radius 348 picometers (van der Waals radius) 0.85%
boiling point 950 K or 677 °C or 1251 °F 0.85%
cas number 7440-73-5 0.85%
cas number of (cl2) - 99.15%
category Alkali metals 5.08%
crystal structure BCC (body centered cubic) 5.93%
density 2.48 g/cm3 0.85%
electronegativity 0.7 (Pauling scale) 0.85%
electronic configuration [Rn] 7s1 0.85%
electrons 87 0.85%
electrons arrangement 2, 8, 18, 32, 18, 8, 1 0.85%
main isotopes 123Fr 0.85%
melting point 300 K or 27 °C or 81 °F 0.85%
neutrons 136 1.69%
position Group: 1, Period: 7, Block: s 0.85%
rarity BROWNIAN-MANIACS 33.33%
state Solid 72.88%
sublimation point - 99.15%
symbol Fr 0.85%
valence electrons 1 5.93%
who discovered Marguerite Perey (in 1939) 0.85%

Total Rarity Score: 2013.33

Rarity: #43/354

Francium

Collection: Bohring Atoms