Atomic number:87

Group numbers:1

Period:7

Electronic configuration:[Rn] 7s¹

Formal oxidation number:+1

Electronegativities:0.7

Atomic radius / pm:282

Relative atomic mass:[223]

 

Francium was discovered by Marguerite Perey (FR) in 1939. Named for France, the nation of its discovery. It is a highly rare and unstable, radioactive metal. Its chemical properties are similar to caesium. Francium is formed from the decay of actinium. It can be produced by bombarding radium or astatine with neutrons. Since its isotopes have such short half-lives there are no commercially significant compounds of francium.

Density / g dm^-3:-

Molar volume / cm³mol^-1:-

Electrical resistivity / μΩcm:- (20 °C)

Thermal conductivity / W m^-1K^-1:15

Melting point / °C:27

Boiling point / °C:677

Heat of fusion / kJ mol^-1:-

Heat of vaporization / kJ mol^-1:-

Heat of atomization / kJ mol^-1:75

1st ionization energy / kJ mol^-1:392.96

2nd ionization energy / kJ mol^-1:-

3rd ionization energy / kJ mol^-1:-

in the atmosphere / ppm:-

in the Earth's crust / ppm:-

in the oceans / ppm:-