Technétium (Tc, Z = 43)
Métal de transition Bloc d Groupe 7 Période 5 Solide (CNTP)
Technetium (/tɛkˈniːʃiəm/) is a chemical element with symbol Tc and atomic number 43. It is the element with the lowest atomic number in the periodic table that has no stable isotopes:every form of it is radioactive. Nearly all technetium is produced synthetically, and only minute amounts are found in nature.
Découvreur : Emilio Segrè
Propriétés physiques
- Masse atomique standard
- 98,00 u
- Densité
- 11,00 g/cm³
- Point de fusion
- 2 430,0 K
- Point d'ébullition
- 4 538,0 K
- Chaleur molaire
- 24,27 J·mol⁻¹·K⁻¹
- Électronégativité (Pauling)
- 1,900
- Affinité électronique
- 53,00 kJ/mol
- Énergies d'ionisation
- 702 ; 1 470 ; 2 850 kJ/mol
- Configuration électronique
- [Kr] 4d5 5s2
- Électrons par couche
- K : 2 · L : 8 · M : 18 · N : 13 · O : 2
- Aspect
- shiny gray metal
Correspondance ANU historique / conjectural
Comptage de la Chimie Occulte (1908) : 1 802 ANU (atomes ultimes), soit N/18 = 100,11 — masse « noologique » à comparer à la masse standard 98,000 u et à l'isotope dominant 97Tc. Coefficient k(Z) = 0,985
Matériel historique et conjectural — voir la page Pont ANU ↔ Nucléides.
Isotopes (40)
| Nucléide | A | N | Masse (u) | Abondance (%) | Demi-vie | Spin | Parité | Magique |
|---|---|---|---|---|---|---|---|---|
| 83Tc | 83 | 40 | 82,966377 | — | stable | 1/2 | ⁻ | — |
| 84Tc | 84 | 41 | 83,959527 | — | stable | 1 | ⁺ | — |
| 85Tc | 85 | 42 | 84,950778 | — | stable | 1/2 | ⁻ | — |
| 86Tc | 86 | 43 | 85,944637 | — | 55 ms | 0 | ⁺ | — |
| 87Tc | 87 | 44 | 86,938067 | — | 2.14 s | 9/2 | ⁺ | — |
| 88Tc | 88 | 45 | 87,933794 | — | 6.4 s | 2 | ⁺ | — |
| 89Tc | 89 | 46 | 88,927649 | — | 12.8 s | 9/2 | ⁺ | — |
| 90Tc | 90 | 47 | 89,924074 | — | 49.2 s | 8 | ⁺ | — |
| 91Tc | 91 | 48 | 90,918425 | — | 3.14 min | 9/2 | — | |
| 92Tc | 92 | 49 | 91,915270 | — | 4.25 min | 8 | — | |
| 93Tc | 93 | 50 | 92,910245 | — | 2.75 h | 9/2 | ⁺ | N magique |
| 94Tc | 94 | 51 | 93,909652 | — | 293 min | 7 | ⁺ | — |
| 95Tc | 95 | 52 | 94,907652 | — | 19.258 h | 9/2 | ⁺ | — |
| 96Tc | 96 | 53 | 95,907867 | — | 4.28 j | 7 | ⁺ | — |
| 97Tc | 97 | 54 | 96,906361 | — | 4.21 Ma | 9/2 | ⁺ | — |
| 98Tc | 98 | 55 | 97,907211 | — | 4.2 Ma | 6 | ⁺ | — |
| 99Tc | 99 | 56 | 98,906250 | — | 211.1 ka | 9/2 | ⁺ | — |
| 100Tc | 100 | 57 | 99,907653 | — | 15.46 s | 1 | ⁺ | — |
| 101Tc | 101 | 58 | 100,907305 | — | 14.22 min | 9/2 | ⁺ | — |
| 102Tc | 102 | 59 | 101,909207 | — | 5.28 s | 1 | ⁺ | — |
| 103Tc | 103 | 60 | 102,909174 | — | 54.2 s | 5/2 | ⁺ | — |
| 104Tc | 104 | 61 | 103,911434 | — | 18.3 min | 3 | ⁻ | — |
| 105Tc | 105 | 62 | 104,911662 | — | 7.64 min | 3/2 | ⁻ | — |
| 106Tc | 106 | 63 | 105,914357 | — | 35.6 s | 1 | — | |
| 107Tc | 107 | 64 | 106,915458 | — | 21.2 s | 3/2 | ⁻ | — |
| 108Tc | 108 | 65 | 107,918493 | — | 5.17 s | 2 | — | |
| 109Tc | 109 | 66 | 108,920254 | — | 905 ms | 5/2 | ⁺ | — |
| 110Tc | 110 | 67 | 109,923741 | — | 900 ms | 2 | ⁺ | — |
| 111Tc | 111 | 68 | 110,925899 | — | 350 ms | 5/2 | ⁺ | — |
| 112Tc | 112 | 69 | 111,929942 | — | 323 ms | 2 | ⁺ | — |
| 113Tc | 113 | 70 | 112,932569 | — | 152 ms | 5/2 | ⁺ | — |
| 114Tc | 114 | 71 | 113,937090 | — | 121 ms | 5 | ⁺ | — |
| 115Tc | 115 | 72 | 114,940100 | — | 78 ms | 5/2 | ⁺ | — |
| 116Tc | 116 | 73 | 115,945020 | — | 57 ms | 2 | ⁺ | — |
| 117Tc | 117 | 74 | 116,948320 | — | 44.5 ms | 5/2 | ⁺ | — |
| 118Tc | 118 | 75 | 117,953526 | — | 30 ms | 2 | ⁺ | — |
| 119Tc | 119 | 76 | 118,956876 | — | 22 ms | 5/2 | ⁺ | — |
| 120Tc | 120 | 77 | 119,962426 | — | 21 ms | 3 | ⁺ | — |
| 121Tc | 121 | 78 | 120,966140 | — | 22 ms | 5/2 | ⁺ | — |
| 122Tc | 122 | 79 | 121,971760 | — | — | 1 | ⁺ | — |
Liseré coloré en première colonne : vert = stable, jaune = demi-vie > 1 an, orange > 1 jour, rouge < 1 jour.