Praséodyme (Pr, Z = 59)
Lanthanide Bloc f Groupe 3 Période 6 Solide (CNTP)
Praseodymium is a chemical element with symbol Pr and atomic number 59. Praseodymium is a soft, silvery, malleable and ductile metal in the lanthanide group. It is valued for its magnetic, electrical, chemical, and optical properties.
Découvreur : Carl Auer von Welsbach
Propriétés physiques
- Masse atomique standard
- 140,9 u
- Densité
- 6,770 g/cm³
- Point de fusion
- 1 208,0 K
- Point d'ébullition
- 3 403,0 K
- Chaleur molaire
- 27,20 J·mol⁻¹·K⁻¹
- Électronégativité (Pauling)
- 1,130
- Affinité électronique
- 93,00 kJ/mol
- Énergies d'ionisation
- 527 ; 1 020 ; 2 086 ; 3 761 kJ/mol
- Configuration électronique
- [Xe] 4f3 6s2
- Électrons par couche
- K : 2 · L : 8 · M : 18 · N : 21 · O : 8 · P : 2
- Aspect
- grayish white
Correspondance ANU historique / conjectural
Comptage de la Chimie Occulte (1908) : 2 527 ANU (atomes ultimes), soit N/18 = 140,39 — masse « noologique » à comparer à la masse standard 140,908 u et à l'isotope dominant 141Pr. Coefficient k(Z) = 0,941
Matériel historique et conjectural — voir la page Pont ANU ↔ Nucléides.
Isotopes (41)
| Nucléide | A | N | Masse (u) | Abondance (%) | Demi-vie | Spin | Parité | Magique |
|---|---|---|---|---|---|---|---|---|
| 121Pr | 121 | 62 | 120,955393 | — | 12 ms | 3/2 | — | |
| 122Pr | 122 | 63 | 121,951927 | — | — | — | — | |
| 123Pr | 123 | 64 | 122,946076 | — | — | 3/2 | ⁺ | — |
| 124Pr | 124 | 65 | 123,942940 | — | 1.2 s | — | — | |
| 125Pr | 125 | 66 | 124,937659 | — | 3.3 s | 3/2 | ⁺ | — |
| 126Pr | 126 | 67 | 125,935240 | — | 3.12 s | 4 | — | |
| 127Pr | 127 | 68 | 126,930710 | — | 4.2 s | 3/2 | ⁺ | — |
| 128Pr | 128 | 69 | 127,928791 | — | 2.85 s | 3 | ⁺ | — |
| 129Pr | 129 | 70 | 128,925095 | — | 30 s | 3/2 | ⁺ | — |
| 130Pr | 130 | 71 | 129,923590 | — | 40 s | 6 | — | |
| 131Pr | 131 | 72 | 130,920235 | — | 1.5 min | 3/2 | ⁺ | — |
| 132Pr | 132 | 73 | 131,919240 | — | 1.49 min | 2 | ⁺ | — |
| 133Pr | 133 | 74 | 132,916331 | — | 6.5 min | 5/2 | ⁺ | — |
| 134Pr | 134 | 75 | 133,915697 | — | 17 min | 2 | ⁻ | — |
| 135Pr | 135 | 76 | 134,913112 | — | 24 min | 3/2 | ⁺ | — |
| 136Pr | 136 | 77 | 135,912677 | — | 13.1 min | 2 | ⁺ | — |
| 137Pr | 137 | 78 | 136,910679 | — | 1.28 h | 5/2 | ⁺ | — |
| 138Pr | 138 | 79 | 137,910757 | — | 1.45 min | 1 | ⁺ | — |
| 139Pr | 139 | 80 | 138,908933 | — | 4.41 h | 5/2 | ⁺ | — |
| 140Pr | 140 | 81 | 139,909086 | — | 3.39 min | 1 | ⁺ | — |
| 141Pr | 141 | 82 | 140,907660 | 100,0000 | stable | 5/2 | ⁺ | N magique |
| 142Pr | 142 | 83 | 141,910052 | — | 19.12 h | 2 | ⁻ | — |
| 143Pr | 143 | 84 | 142,910823 | — | 13.57 j | 7/2 | ⁺ | — |
| 144Pr | 144 | 85 | 143,913311 | — | 17.28 min | 0 | ⁻ | — |
| 145Pr | 145 | 86 | 144,914518 | — | 5.984 h | 7/2 | ⁺ | — |
| 146Pr | 146 | 87 | 145,917688 | — | 24.09 min | 2 | ⁻ | — |
| 147Pr | 147 | 88 | 146,919007 | — | 13.39 min | 3/2 | ⁺ | — |
| 148Pr | 148 | 89 | 147,922130 | — | 2.29 min | 1 | ⁻ | — |
| 149Pr | 149 | 90 | 148,923736 | — | 2.26 min | 5/2 | ⁺ | — |
| 150Pr | 150 | 91 | 149,926676 | — | 6.19 s | 1 | ⁻ | — |
| 151Pr | 151 | 92 | 150,928309 | — | 18.9 s | 3/2 | ⁻ | — |
| 152Pr | 152 | 93 | 151,931553 | — | 3.57 s | 4 | ⁺ | — |
| 153Pr | 153 | 94 | 152,933904 | — | 4.28 s | 3/2 | ⁻ | — |
| 154Pr | 154 | 95 | 153,937885 | — | 2.3 s | 3 | ⁺ | — |
| 155Pr | 155 | 96 | 154,940509 | — | 1.47 s | 3/2 | ⁻ | — |
| 156Pr | 156 | 97 | 155,944767 | — | 444 ms | 1 | ⁺ | — |
| 157Pr | 157 | 98 | 156,948003 | — | 307 ms | 3/2 | ⁻ | — |
| 158Pr | 158 | 99 | 157,952603 | — | 181 ms | 5 | ⁻ | — |
| 159Pr | 159 | 100 | 158,956232 | — | 134 ms | 3/2 | ⁻ | — |
| 160Pr | 160 | 101 | 159,961138 | — | 170 ms | 1 | ⁺ | — |
| 161Pr | 161 | 102 | 160,965121 | — | — | 3/2 | ⁻ | — |
Liseré coloré en première colonne : vert = stable, jaune = demi-vie > 1 an, orange > 1 jour, rouge < 1 jour.