Asked by sc.sallan | 27th Nov, 2009, 09:06: PM

Expert Answer:

There are 34 known isotopes of francium ranging in atomic mass from 199 to 232. Francium-223 and francium-221 are the only isotopes that occur in nature.

Francium-223 is the most stable isotope with a half-life of 21.8 minutes .It is the only isotope of francium with longest half-life ever discovered or synthesized. There are other isotopes of francium with very short half life like Francium-221 with a half-life of 4.8 minutes, francium-215, with a half-life of 0.12 μs.

Answered by  | 30th Nov, 2009, 09:54: AM

Queries asked on Sunday & after 7pm from Monday to Saturday will be answered after 12pm the next working day.