Francium

Francium is a highly radioactive and extremely rare alkali metal.

It is the second rarest naturally occurring element on Earth (after astatine).

Discovered by Marguerite Perey in 1939 in France.

SymbolFr
Atomic Number87
Group1 (Alkali Metals)
Period7
Blocks-block

Key Features

  • Francium is extremely unstable, with its most stable isotope (Fr-223) having a half-life of only 22 minutes.
  • Produced by the alpha decay of actinium-227.
  • Due to its radioactivity and rarity, it has no practical commercial use.
  • Chemically, it is expected to behave like other alkali metals (e.g., reacts violently with water), but detailed studies are limited due to its short lifespan and scarcity.
Francium Sample

Interesting Facts

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Despite being an alkali metal, francium has never been seen in bulk—only small atoms at a time in research labs.