Francium
87
Fr
Skupina
1
Perióda
7
Orbitál
s
Protóny
Elektróny
Neutróny
87
87
136
Hlavné vlastnosti
Protónové číslo
87
Atómová hmotnosť
[223]
Hmotnostné číslo
223
Kategória
Alkalické kovy
Farba
Strieborná
Rádioaktívny
Áno
Francium was named after France
Kryštálová sústava
n/a
História
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.
Elektróny v obale
2, 8, 18, 32, 18, 8, 1
Elektrónová konfigurácia
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
Fyzikálne vlastnosti
Skupenstvo
Tuhé látky
Hustota
1,87 g/cm3
Teplota topenia
296,15 K | 23 °C | 73,4 °F
Teplota varu
950,15 K | 677 °C | 1250,6 °F
Skupenské teplo topenia
2 kJ/mol
Skupenské teplo varu
65 kJ/mol
Tepelná kapacita
-
Množstvo v zemskej kôre
n/a
Množstvo vo vesmíre
n/a
Registračné číslo CAS
7440-73-5
PubChem CID číslo
n/a
Atómové vlastnosti
Atómový polomer
260 pm
Kovalentný polomer
348 pm
Elektronegativita
0,7 (Paulingova stupnica)
Ionizačný potenciál
4,0727 eV
Atómový objem
71,07 cm3/mol
Tepelná vodivosť
0,15 W/cm·K
Oxidačné stavy
1
Aplikácie
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
Izotopy
Stabilné izotopy
-Nestabilné izotopy
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