Francij
87
Fr
Skupina
1
Perioda
7
Blok
s
Protoni
Elektroni
Neutroni
87
87
136
Opća svojstva
Atomski broj
87
Relativna atomska masa
[223]
Maseni broj
223
Kategorija
Alkalijski metali
Boja
Srebrna
Radioaktivan
Da
Francij je imenovan po Francuskoj
Kristalna struktura
n/a
Povijest
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.
Elektrona po ljusci
2, 8, 18, 32, 18, 8, 1
Elektronska konfiguracija
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
Fizikalna svojstva
Agregacijsko stanje
Čvrsto
Gustoća
1,87 g/cm3
Talište
296,15 K | 23 °C | 73,4 °F
Vrelište
950,15 K | 677 °C | 1250,6 °F
Toplina taljenja
2 kJ/mol
Toplina isparavanja
65 kJ/mol
Specifični toplinski kapacitet
-
Zastupljenost u Zemljinoj kori
n/a
Zastupljenost u svemiru
n/a
CAS broj
7440-73-5
PubChem CID broj
n/a
Atomska svojstva
Atomski radijus
260 pm
Kovalentni radijus
348 pm
Elektronegativnost
0,7 (Paulingova ljestvica)
Potencijal ionizacije
4,0727 eV
Atomski volumen
71,07 cm3/mol
Toplinska vodljivost
0,15 W/cm·K
Stanja oksidacije
1
Primjene
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
Izotopi
Stabilni izotopi
-Nestabilni izotopi
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