Lawrencium (Lr, Z = 103)
103
Lr
266,000 u
Actinide Bloc d Groupe 3 Période 7 Solide (CNTP)
Lawrencium is a synthetic chemical element with chemical symbol Lr (formerly Lw) and atomic number 103. It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements. A radioactive metal, lawrencium is the eleventh transuranic element and is also the final member of the actinide series.
Découvreur : Lawrence Berkeley National Laboratory
Propriétés physiques
- Masse atomique standard
- 266,0 u
- Densité
- —
- Point de fusion
- 1 900,0 K
- Point d'ébullition
- —
- Chaleur molaire
- —
- Électronégativité (Pauling)
- 1,300
- Affinité électronique
- -30,04 kJ/mol
- Énergies d'ionisation
- 470 kJ/mol
- Configuration électronique
- [Rn] 5f14 7s2 7p1
- Électrons par couche
- K : 2 · L : 8 · M : 18 · N : 32 · O : 32 · P : 8 · Q : 3
Isotopes (16)
| Nucléide | A | N | Masse (u) | Abondance (%) | Demi-vie | Spin | Parité | Magique |
|---|---|---|---|---|---|---|---|---|
| 251Lr | 251 | 148 | 251,094289 | — | — | — | — | |
| 252Lr | 252 | 149 | 252,095048 | — | 369 ms | 7 | ⁻ | — |
| 253Lr | 253 | 150 | 253,095034 | — | 632 ms | 7/2 | ⁻ | — |
| 254Lr | 254 | 151 | 254,096239 | — | 12 s | 4 | ⁺ | — |
| 255Lr | 255 | 152 | 255,096562 | — | 31.1 s | 1/2 | ⁻ | — |
| 256Lr | 256 | 153 | 256,098494 | — | 27.9 s | 0 | ⁻ | — |
| 257Lr | 257 | 154 | 257,099480 | — | 6 s | 7/2 | ⁻ | — |
| 258Lr | 258 | 155 | 258,101753 | — | 3.92 s | — | — | |
| 259Lr | 259 | 156 | 259,102900 | — | 6.2 s | 1/2 | ⁻ | — |
| 260Lr | 260 | 157 | 260,105504 | — | 3 min | — | — | |
| 261Lr | 261 | 158 | 261,106879 | — | 39 min | 1/2 | ⁻ | — |
| 262Lr | 262 | 159 | 262,109615 | — | — | — | — | |
| 263Lr | 263 | 160 | 263,111293 | — | — | 1/2 | ⁻ | — |
| 264Lr | 264 | 161 | 264,114198 | — | — | — | — | |
| 265Lr | 265 | 162 | 265,116193 | — | — | 1/2 | ⁻ | — |
| 266Lr | 266 | 163 | 266,119874 | — | 22 h | — | — |
Liseré coloré en première colonne : vert = stable, jaune = demi-vie > 1 an, orange > 1 jour, rouge < 1 jour.