Francij
87
Fr
Skupina
1
Perioda
7
Blok
s
Protons
Electrons
Neutrons
87
87
136
General Properties
Vrstno število
87
Atomska teža
[223]
Mass Number
223
Kategorija
Alkalijske kovine
Barva
Silver
Radioactive
Da
Francium was named after France
Kristalna struktura
n/a
Zgodovina
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.
Electrons per shell
2, 8, 18, 32, 18, 8, 1
Razporeditev elektronov
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
Physical Properties
Faza snovi
Trdnina
Gostota
1,87 g/cm3
Tališče
296,15 K | 23 °C | 73,4 °F
Vrelišče
950,15 K | 677 °C | 1250,6 °F
Talilna toplota
2 kJ/mol
Izparilna toplota
65 kJ/mol
Toplotna kapaciteta
-
Abundance in Earth's crust
n/a
Abundance in Universe
n/a
CAS Number
7440-73-5
PubChem CID Number
n/a
Atomic Properties
Atomski polmer
260 pm
Kovalentni polmer
348 pm
Elektronegativnost
0,7 (Paulingova lestvica)
Ionization Potential
4,0727 eV
Atomic Volume
71,07 cm3/mol
Toplotna prevodnost
0,15 W/cm·K
Oksidacijska stanja
1
Applications
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
Isotopes
Stable Isotopes
-Unstable Isotopes
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