Structure of Francium

    In Francium’s nucleus there are 87 protons and 136 neutrons.  In the seven electron cloud shells there are 87 electrons.  Part of Francium’s unique characteristics is the one valance electron in the seventh shell.  The makes Francium part of the Alkali metal group, it also make the element very quick to react to rid itself, making a stable outer shell.   

Isotopes

There is only one naturally occuring isotope of Francium, Francium 223.  It has a half life of 22 minutes and decays into Radium (3).

This is a list of synthetic isotopes as well as the level of radiation produced.

Visit here for list: http://environmentalchemistry.com/yogi/periodic/Fr-pg2.htm