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Thursday, June 16, 2016

Francium chemical element

Francium was discovered by the french chemist Marguerite Perey.
The chemical symbol is Francium Fr and its atomic number is 87.
We find it listed in the periodic table of elements in group 1 and 7 period and block s.
The Francium belongs to the family or chemical series of alkali metals such as for example cesium. This element is Radioactive, Francium came from Francia which means France.


Francium chemical element



Atomic number (Z) 87
Group, block group 1 (alkali metals), s-block
Period: period 7
Element category: alkali metal
Standard atomic weight (Ar) (223)
Electron configuration: [Rn] 7s1
per shell: 2, 8, 18, 32, 18, 8, 1

Physical properties:
Phase: solid presumably
Melting point: 300 K (27 °C, 80 °F)
Boiling point: 950 K (677 °C, 1250 °F)
Density near r.t.: 1.87 g/cm3 (extrapolated)
Heat of fusion ca. 2 kJ/mol
Heat of vaporization: ca. 65 kJ/mol

Atomic properties:
Oxidation states: +1 (a strongly basic oxide)
Electronegativity: Pauling scale: 0.7
Ionization energies 1st: 393[1] kJ/mol
Covalent radius: 260 pm
Van der Waals radius: 348 pm

Crystal structure: body-centered cubic
Thermal conductivity: 15 W/(m•K) (extrapolated)
Electrical resistivity: 3 µΩ•m (calculated)