Францијум
87
Fr
Група
1
Периода
7
Блок
s
Протони
Електрони
Неутрони
87
87
136
Општа својства
Атомски број
87
Атомска маса
[223]
Масени број
223
Категорија
Алкални метали
Боја
Сребрена
Радиоактиван
Да
Francium was named after France
Кристална структура
н/д
Историја
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.
Електрони по љусци
2, 8, 18, 32, 18, 8, 1
Електронска конфигурација
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
Физичка својства
Стање
Чвсрто
Густина
1,87 g/cm3
Температура топљења
296,15 K | 23 °C | 73,4 °F
Температура кључања
950,15 K | 677 °C | 1250,6 °F
Топлота топљења
2 kJ/mol
Топлота испаравања
65 kJ/mol
Специфична топлота
-
Заступљеност у Земљиној кори
н/д
Заступљеност у Космосу
н/д
CAS број
7440-73-5
ПубЦхем ЦИД број
н/д
Атомска својства
Атомски радијус
260 pm
Ковалентни радијус
348 pm
Електронегативност
0,7 (Полингова скала)
Јонизујући потенцијал
4,0727 eV
Молска запремина
71,07 cm3/mol
Топлотна проводљивост
0,15 W/cm·K
Оксидациона стања
1
Примена
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
Изотопи
Стабилни изотопи
-Нестабилни изотопи
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