Fr - Francium - periodic table of the elements

Rare, reactive and radioactive, francium is hard to come by - only about a tenth of a mole exists at any time. Possibly observed in 1931 by Fred Allison, who called it virginium, the element was discovered and confirmed in 1939 by Marguerite Perey, in decay products of actinium.

Atomic number	-	87		Density	g/mL	1	.87
Atomic weight	u	223	.0197	Melting point	K	300	.2
Bonding radius	A	-		Boiling point	K	950
Atomic radius	A	-		Heat of vaporization	kJ/mol	-
Ionization Potential	V	4	.08	Heat of fusion	kJ/mol	-
Electronegativity	-	0	.7	Specific heat	J/gK	-
The oxide is a strong base.				Crystal are body centered cubic.
Electron configuration: [Rn] 7s¹

Other elements of the periodic table

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

H He

Li Be B C N O F Ne

Na Mg Al Si P S Cl Ar

K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr

Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe

Cs Ba La * Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn

Fr Ra Ac ** Rf Db Sg Bh Hs Mt 110 111 112 113

Lanthanides* Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu

Actinides ** Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr