Source of the photo
http://www.webelements.com/francium/
Author of the description
Gruiz Katalin
Atomic number | 87 |
Atomic mass | 233 g.mol -1 |
Electronegativity | 0.7 |
Density | 1,87 g.cm-3 |
Melting point | 27 °C |
Boiling point | 677 °C |
Vanderwaals radius | unknown |
Ionic radius | unknown |
Isotopes | 34 |
Electronic shell | [ Rn ] 7s1 |
Energy of first ionisation | 375 kJ.mol -1 |
Discovered by | Marguerite Perey in 19 |
Francium is extremely rare. Because of this its chemical and physical properties are not known. It has been studied by radiochemical techniques, which show that its most stable state is the ion Fr+. Francium is the least electronegative of all the known elements.
Applications
No use has been found for what little francium can be produced.
Source of description