Francium
87
Fr
Gruppe
1
Periode
7
Block
s
Protonen
Elektronen
Neutronen
87
87
136
Generelle Eigenschaften
Ordnungszahl
87
Atommasse
[223]
Massenzahl
223
Kategorie
Alkalimetalle
Farbe
Silber
Radioaktiv
Ja
Francium wurde nach Frankreich benannt
Kristallstruktur
n/a
Geschichte
Francium was discovered in 1939 by Marguerite Perey of the Curie Institute in Paris, France.
It was discovered when she was researching the radioactive decay of actinium-227.
Marguerite Perey discovered that francium-223 is made naturally when actinium-227 emits an alpha-particle.
It was discovered when she was researching the radioactive decay of actinium-227.
Marguerite Perey discovered that francium-223 is made naturally when actinium-227 emits an alpha-particle.
Elektronen pro Schale
2, 8, 18, 32, 18, 8, 1
Elektronenkonfiguration
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
Physikalische Eigenschaften
Aggregatzustand
Fest
Dichte
1,87 g/cm3
Schmelzpunkt
296,15 K | 23 °C | 73,4 °F
Siedepunkt
950,15 K | 677 °C | 1250,6 °F
Schmelzwärme
2 kJ/mol
Verdampfungswärme
65 kJ/mol
Spezifische Wärmekapazität
-
Häufigkeit in der Erdkruste
n/a
Häufigkeit im Universum
n/a
CAS-Nummer
7440-73-5
PubChem CID-Nummer
n/a
Atomeigenschaften
Atomradius
260 pm
Kovalenter Radius
348 pm
Elektronegativität
0,7 (Pauling-Skala)
Ionisierungsenergie
4,0727 eV
Molares Volumen
71,07 cm3/mol
Wärmeleitfähigkeit
0,15 W/cm·K
Oxidationszustände
1
Anwendung
Due to its instability and rarity, there are no commercial applications for francium.
It has been used for research purposes in the fields of biology and of atomic structure.
Its use as a potential diagnostic aid for various cancers has also been explored, but this application has been deemed impractical.
It has been used for research purposes in the fields of biology and of atomic structure.
Its use as a potential diagnostic aid for various cancers has also been explored, but this application has been deemed impractical.
Francium is highly radioactive
Isotope
Stabile Isotope
-Instabile Isotope
199Fr, 200Fr, 201Fr, 202Fr, 203Fr, 204Fr, 205Fr, 206Fr, 207Fr, 208Fr, 209Fr, 210Fr, 211Fr, 212Fr, 213Fr, 214Fr, 215Fr, 216Fr, 217Fr, 218Fr, 219Fr, 220Fr, 221Fr, 222Fr, 223Fr, 224Fr, 225Fr, 226Fr, 227Fr, 228Fr, 229Fr, 230Fr, 231Fr, 232Fr