- Atomic Radius (Å)
Francium is a chemical element with symbol Fr and atomic number 87. It used to be known as eka-caesium and actinium K. It is the second-least electronegative element, behind only caesium. Francium is a highly radioactive metal that decays into astatine, radium, and radon.
87
Atomic Number
223 u
Atomic Mass
300.15 K
Melting Point
950 K
Boiling Point
1.87 g/cm³
Density
null Å
Atomic Radius
2.6 Å
Covalent Radius
0.7
Electronegativity
4.07 eV
First Ionization Energy
46.89
Electron Affinity
7
Number of Shells
1
Electron Valency
2, 8, 18, 32, 18, 8, 1
Electron Shell Occupations
null J/g
Specific Heat