Template:Infobox francium

Francium, 00Fr
Francium
Pronunciation/ˈfrænsiəm/ (FRAN-see-əm)
Mass number[223]
Francium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson
Cs

Fr

(Uue)
radonfranciumradium
Groupgroup 1: hydrogen and alkali metals
Periodperiod 7
Block  s-block
Electron configuration[Rn] 7s1
Electrons per shell2, 8, 18, 32, 18, 8, 1
Physical properties
Phase at STPsolid
Melting point300 K ​(27 °C, ​81 °F)
Boiling point950 K ​(677 °C, ​1251 °F)
Density (near r.t.)2.48 g/cm3 (estimated)[1]
Vapor pressure (extrapolated)
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 404 454 519 608 738 946
Atomic properties
Oxidation states+1 (expected to have a strongly basic oxide)
ElectronegativityPauling scale: >0.79
Ionization energies
  • 1st: 393 kJ/mol[2]
Covalent radius260 pm (extrapolated)
Van der Waals radius348 pm (extrapolated)
Other properties
Natural occurrencefrom decay
Crystal structurebody-centered cubic (bcc)
Body-centered cubic crystal structure for francium

(extrapolated)
Thermal conductivity15 W/(m⋅K) (extrapolated)
Electrical resistivity3 µΩ⋅m (calculated)
Magnetic orderingParamagnetic
CAS Number7440-73-5
History
Namingafter France, homeland of the discoverer
Discovery and first isolationMarguerite Perey (1939)
Isotopes of francium
Main isotopes[3] Decay
abun­dance half-life (t1/2) mode pro­duct
212Fr synth 20.0 min β+ 212Rn
α 208At
221Fr trace 4.8 min α 217At
222Fr synth 14.2 min β 222Ra
223Fr trace 22.00 min β 223Ra
α 219At
 Category: Francium
| references

References

  1. Lavrukhina, Avgusta Konstantinovna; Pozdnyakov, Aleksandr Aleksandrovich (1970). Analytical Chemistry of Technetium, Promethium, Astatine, and Francium. Translated by R. Kondor. Ann Arbor–Humphrey Science Publishers. p. 269. ISBN 978-0-250-39923-9.
  2. ISOLDE Collaboration, J. Phys. B 23, 3511 (1990) (PDF online)
  3. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.