Франциум

87
Fr
Група
1
Периода
7
блок
s
Protons
Electrons
Neutrons
87
87
136
Општи Својства
Атомски број
87
Атомска тежина
[223]
Mass Number
223
Category
Алкален метал
Color
Silver
Radioactive
Да
Francium was named after France
Кристална структура
Нема одговор
History
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.
Electrons per shell
2, 8, 18, 32, 18, 8, 1
Електронска конфигурација
[Rn] 7s1
Fr
Francium was the last element discovered in nature, rather than by synthesis
Физички Својства
Фаза
Solid
Густина
1,87 g/cm3
Точка на топење
296,15 K | 23 °C | 73,4 °F
Точка на вриење
950,15 K | 677 °C | 1250,6 °F
Топлина на топење
2 kJ/mol
Топлина на испарување
65 kJ/mol
Specific Heat Capacity
-
Abundance in Earth's crust
Нема одговор
Abundance in Universe
Нема одговор
Illustration
Кредити на слика: Images-of-elements
Illustration of francium
CAS Number
7440-73-5
PubChem CID Number
Нема одговор
Атомски Својства
Атомски полупречник
260 pm
Ковалентен полупречник
348 pm
Електронегативност
0,7 (Полингова скала)
Ionization Potential
4,0727 eV
Atomic Volume
71,07 cm3/mol
Thermal Conductivity
0,15 W/cm·K
Oxidation States
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.
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