Periodic Table of Elements

87

Francium

223.02

Francium was discovered by Marguerite Catherine Perey, a French chemist, in 1939 while analyzing actinium's decay sequence.

Name: Francium
Symbol: Fr
Atomic number: 87
Atomic weight: 223.02
State:solid
Group, period, block: 1, 7, s
Color: metallic
Classification: alkali metal
Electron configuration: 7s1
2,8,18,32,18,8,1

Physical properties

Density: 1.87 g/cm-3
Melting point: 300 K,27 C,80 F
Boiling point: 950 K,677 C,1250 F

Atomic properties

Oxidation states: 1
Electronegativity: 0.7 (Pauling scale)
Ionization energies: 1st: 380 kJmol-1
Covalent radius: 260 pm
Van der Waals radius: 348 pm
  • Fr
  • Electron Configuration

Isotopes

Francium has no stable isotopes. Its most stable isotope is 223Fr with a half-life of 22 minutes.