钫
87
Fr
族
1
週期
7
區
s
個質子
電子
個中子
87
87
136
一般屬性
原子序數
87
標準原子質量
[223]
品質編號
223
類別
鹼金屬
顏色
銀色
放射性
是
Francium was named after France
晶體結構
無法計量
歷史
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.
每個外殼的電子
2, 8, 18, 32, 18, 8, 1
電子排布
[Rn] 7s1
Francium was the last element discovered in nature, rather than by synthesis
物理性質
物態
固體
密度
1.87 g/cm3
熔點
296.15 K | 23 °C | 73.4 °F
沸點
950.15 K | 677 °C | 1250.6 °F
熔化熱
2 kJ/mol
汽化熱
65 kJ/mol
比熱容
-
地殼豐度
無法計量
宇宙豐度
無法計量
CAS 編號
7440-73-5
Pubchem CID 編號
無法計量
原子性質
原子半徑
260 pm
共價半徑
348 pm
電負性
0.7 (鲍林标度)
電離電位
4.0727 eV
原子體積
71.07 cm3/mol
熱導率
0.15 W/cm·K
氧化態
1
應用
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
同位素
穩定同位素
-不穩定同位素
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