Mendélévium (Md, Z = 101)
101
Md
258,000 u
Actinide Bloc f Groupe 3 Période 7 Solide (CNTP)
Mendelevium is a synthetic element with chemical symbol Md (formerly Mv) and atomic number 101. A metallic radioactive transuranic element in the actinide series, it is the first element that currently cannot be produced in macroscopic quantities through neutron bombardment of lighter elements. It is the antepenultimate actinide and the ninth transuranic element.
Découvreur : Lawrence Berkeley National Laboratory
Propriétés physiques
- Masse atomique standard
- 258,0 u
- Densité
- —
- Point de fusion
- 1 100,0 K
- Point d'ébullition
- —
- Chaleur molaire
- —
- Électronégativité (Pauling)
- 1,300
- Affinité électronique
- 93,91 kJ/mol
- Énergies d'ionisation
- 635 kJ/mol
- Configuration électronique
- [Rn] 5f13 7s2
- Électrons par couche
- K : 2 · L : 8 · M : 18 · N : 32 · O : 31 · P : 8 · Q : 2
Isotopes (19)
| Nucléide | A | N | Masse (u) | Abondance (%) | Demi-vie | Spin | Parité | Magique |
|---|---|---|---|---|---|---|---|---|
| 244Md | 244 | 143 | 244,081157 | — | 0.36 s | 3 | ⁺ | — |
| 245Md | 245 | 144 | 245,080864 | — | 0.38 s | 7/2 | ⁻ | — |
| 246Md | 246 | 145 | 246,081713 | — | 0.92 s | 1 | ⁻ | — |
| 247Md | 247 | 146 | 247,081520 | — | 1.19 s | 7/2 | ⁻ | — |
| 248Md | 248 | 147 | 248,082607 | — | 7 s | — | — | |
| 249Md | 249 | 148 | 249,082857 | — | 25.6 s | 7/2 | ⁻ | — |
| 250Md | 250 | 149 | 250,084165 | — | 54 s | 2 | ⁻ | — |
| 251Md | 251 | 150 | 251,084774 | — | 4.21 min | 7/2 | ⁻ | — |
| 252Md | 252 | 151 | 252,086385 | — | 2.3 min | 1 | ⁺ | — |
| 253Md | 253 | 152 | 253,087143 | — | 12 min | 7/2 | ⁻ | — |
| 254Md | 254 | 153 | 254,089590 | — | 10 min | 0 | ⁻ | — |
| 255Md | 255 | 154 | 255,091082 | — | 27 min | 7/2 | ⁻ | — |
| 256Md | 256 | 155 | 256,093888 | — | 77.7 min | 1 | ⁻ | — |
| 257Md | 257 | 156 | 257,095537 | — | 5.52 h | 7/2 | ⁻ | — |
| 258Md | 258 | 157 | 258,098434 | — | 51.59 j | 8 | ⁻ | — |
| 259Md | 259 | 158 | 259,100445 | — | 1.6 h | 7/2 | ⁻ | — |
| 260Md | 260 | 159 | 260,103650 | — | 27.8 j | — | — | |
| 261Md | 261 | 160 | 261,105828 | — | — | 7/2 | ⁻ | — |
| 262Md | 262 | 161 | 262,109144 | — | — | — | — |
Liseré coloré en première colonne : vert = stable, jaune = demi-vie > 1 an, orange > 1 jour, rouge < 1 jour.