Francium
Fr223.01973 g/mol Calculated
Also called eka-cesium, catium and eka-caesium.
The rarest naturally occurring element after astatine: at most a few tens of grams exist in the entire earth's crust at any moment. Element 87.
Sources and notes
- The introductionfrom sourceMoleculeFinder curated
- Other namesfrom sourceWikidataIts English label and aliases on Wikidata.
- Formula and weightcomputedPubChem
- 2D drawingcomputedPubChem structure, drawn by RDKit
Where you encounter it
A pure element or an engineered material, rather than an ingredient in a product.
Sources and notes
- The line abovefrom sourceMoleculeFinder curatedFrom the group the molecule belongs to.
Properties and sources
Calculated by PubChem
- Molecular formula
- Fr
- Molecular weight
- 223.01973 g/mol
Groups it belongs to
- Category
- Element & material
- Family
- Chemical elements
SMILES
[Fr]PubChem CID 6328145 · Wikidata Q671 · InChIKey KLMCZVJOEAUDNE-UHFFFAOYSA-N · Data refreshed
Questions
- What is Francium?
- The rarest naturally occurring element after astatine: at most a few tens of grams exist in the entire earth's crust at any moment. Element 87.
- What kind of molecule is Francium?
- Francium has the formula Fr and a molecular weight of 223.02 g/mol. MoleculeFinder files it under chemical elements, in the element & material group. from sourcefrom sourcefrom sourcefrom source
- What else is Francium called?
- Francium is also called eka-cesium, catium and eka-caesium. from source
Sources and notes
- Calculated valuescomputedPubChemComputed from the structure, so no laboratory conditions apply; complexity is PubChem's own structural score.
- Data refreshedfrom sourceMoleculeFinder2026-11-09