Frankium
87
Fr
Ryhmä
1
Jakso
7
Lohko
s
Protonia
Elektronit
Neutronia
87
87
136
Yleiset ominaisuudet
Järjestysluku
87
Atomipaino
[223]
Massaluku
223
Luokka
Alkalimetallit
Väri
Hopea
Radioaktiivisuus
Kyllä
Francium was named after France
Kiderakenne
Ei saatavilla
Historia
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.
Elektroneja elektronikuorilla
2, 8, 18, 32, 18, 8, 1
Orbitaalirakenne
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
Fyysiset ominaisuudet
Olomuoto
Kiinteä
Tiheys
1,87 g/cm3
Sulamispiste
296,15 K | 23 °C | 73,4 °F
Kiehumispiste
950,15 K | 677 °C | 1250,6 °F
Sulamislämpö
2 kJ/mol
Höyrystymislämpö
65 kJ/mol
Ominaislämpökapasiteetti
-
Esiintyvyys maankuoressa
Ei saatavilla
Esiintyvyys maailmankaikkeudessa
Ei saatavilla
CAS-numero
7440-73-5
PubChem CID-numero
Ei saatavilla
Atomiominaisuudet
Atomisäde
260 pm
Kovalenttisäde
348 pm
Elektronegatiivisuus
0,7 (Paulingin asteikko)
Ionisoitumispotentiaali
4,0727 eV
Moolitilavuus
71,07 cm3/mol
Lämmönjohtavuus
0,15 W/cm·K
Hapetusluvut
1
Käyttö
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
Isotooppi
Vakaat isotoopit
-Epävakaat isotoopit
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