Berkélium (Bk, Z = 97)
97
Bk
247,000 u
Actinide Bloc f Groupe 3 Période 7 Solide (CNTP)
Berkelium is a transuranic radioactive chemical element with symbol Bk and atomic number 97. It is a member of the actinide and transuranium element series. It is named after the city of Berkeley, California, the location of the University of California Radiation Laboratory where it was discovered in December 1949.
Découvreur : Lawrence Berkeley National Laboratory
Propriétés physiques
- Masse atomique standard
- 247,0 u
- Densité
- 14,78 g/cm³
- Point de fusion
- 1 259,0 K
- Point d'ébullition
- 2 900,0 K
- Chaleur molaire
- —
- Électronégativité (Pauling)
- 1,300
- Affinité électronique
- -165,2 kJ/mol
- Énergies d'ionisation
- 601 kJ/mol
- Configuration électronique
- [Rn] 5f9 7s2
- Électrons par couche
- K : 2 · L : 8 · M : 18 · N : 32 · O : 27 · P : 8 · Q : 2
- Aspect
- silvery
Isotopes (22)
| Nucléide | A | N | Masse (u) | Abondance (%) | Demi-vie | Spin | Parité | Magique |
|---|---|---|---|---|---|---|---|---|
| 233Bk | 233 | 136 | 233,056652 | — | 40 s | 3/2 | ⁻ | — |
| 234Bk | 234 | 137 | 234,057322 | — | 20 s | 3 | ⁻ | — |
| 235Bk | 235 | 138 | 235,056651 | — | — | 3/2 | ⁻ | — |
| 236Bk | 236 | 139 | 236,057479 | — | 26 s | 4 | ⁺ | — |
| 237Bk | 237 | 140 | 237,057123 | — | — | 3/2 | ⁻ | — |
| 238Bk | 238 | 141 | 238,058204 | — | 2.4 min | 1 | — | |
| 239Bk | 239 | 142 | 239,058239 | — | — | 7/2 | ⁺ | — |
| 240Bk | 240 | 143 | 240,059758 | — | 4.8 min | 7 | ⁻ | — |
| 241Bk | 241 | 144 | 241,060098 | — | 4.6 min | 7/2 | ⁺ | — |
| 242Bk | 242 | 145 | 242,061999 | — | 7 min | 3 | ⁺ | — |
| 243Bk | 243 | 146 | 243,063006 | — | 4.6 h | 3/2 | ⁻ | — |
| 244Bk | 244 | 147 | 244,065179 | — | 5.02 h | 4 | ⁻ | — |
| 245Bk | 245 | 148 | 245,066360 | — | 4.95 j | 3/2 | ⁻ | — |
| 246Bk | 246 | 149 | 246,068671 | — | 1.8 j | 2 | — | |
| 247Bk | 247 | 150 | 247,070306 | — | 1.38 ka | 3/2 | ⁻ | — |
| 248Bk | 248 | 151 | 248,073142 | — | — | 6 | ⁺ | — |
| 249Bk | 249 | 152 | 249,074983 | — | 327.2 j | 7/2 | ⁺ | — |
| 250Bk | 250 | 153 | 250,078317 | — | 3.212 h | 2 | ⁻ | — |
| 251Bk | 251 | 154 | 251,080761 | — | 55.6 min | 3/2 | ⁻ | — |
| 252Bk | 252 | 155 | 252,084310 | — | 1.8 min | — | — | |
| 253Bk | 253 | 156 | 253,086880 | — | — | 3/2 | ⁻ | — |
| 254Bk | 254 | 157 | 254,090600 | — | — | — | — |
Liseré coloré en première colonne : vert = stable, jaune = demi-vie > 1 an, orange > 1 jour, rouge < 1 jour.