Radon (Rn, Z = 86)
Gaz noble Bloc p Groupe 18 Période 6 Gaz (CNTP)
Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as a decay product of radium. Its most stable isotope, 222Rn, has a half-life of 3.8 days.
Découvreur : Friedrich Ernst Dorn
Propriétés physiques
- Masse atomique standard
- 222,0 u
- Densité
- 9,730 g/L
- Point de fusion
- 202,0 K
- Point d'ébullition
- 211,5 K
- Chaleur molaire
- —
- Électronégativité (Pauling)
- 2,200
- Affinité électronique
- -68,00 kJ/mol
- Énergies d'ionisation
- 1 037 kJ/mol
- Configuration électronique
- [Xe] 4f14 5d10 6s2 6p6
- Électrons par couche
- K : 2 · L : 8 · M : 18 · N : 32 · O : 18 · P : 8
- Aspect
- colorless gas, occasionally glows green or red in discharge tubes
Correspondance ANU historique / conjectural
Comptage de la Chimie Occulte (1908) : 3 990 ANU (atomes ultimes), soit N/18 = 221,67 — masse « noologique » à comparer à la masse standard 222,000 u et à l'isotope dominant 222Rn. Coefficient k(Z) = 0,890
Matériel historique et conjectural — voir la page Pont ANU ↔ Nucléides.
Isotopes (39)
| Nucléide | A | N | Masse (u) | Abondance (%) | Demi-vie | Spin | Parité | Magique |
|---|---|---|---|---|---|---|---|---|
| 193Rn | 193 | 107 | 193,009708 | — | 1.15 ms | 3/2 | ⁻ | — |
| 194Rn | 194 | 108 | 194,006146 | — | 780 µs | 0 | ⁺ | — |
| 195Rn | 195 | 109 | 195,005422 | — | 7 ms | 3/2 | ⁻ | — |
| 196Rn | 196 | 110 | 196,002120 | — | 4.7 ms | 0 | ⁺ | — |
| 197Rn | 197 | 111 | 197,001621 | — | 54 ms | 3/2 | ⁻ | — |
| 198Rn | 198 | 112 | 197,998679 | — | 64.4 ms | 0 | ⁺ | — |
| 199Rn | 199 | 113 | 198,998325 | — | 590 ms | 3/2 | ⁻ | — |
| 200Rn | 200 | 114 | 199,995705 | — | 1.09 s | 0 | ⁺ | — |
| 201Rn | 201 | 115 | 200,995591 | — | 7 s | 3/2 | ⁻ | — |
| 202Rn | 202 | 116 | 201,993264 | — | 9.7 s | 0 | ⁺ | — |
| 203Rn | 203 | 117 | 202,993361 | — | 44.2 s | 3/2 | ⁻ | — |
| 204Rn | 204 | 118 | 203,991444 | — | 1.242 min | 0 | ⁺ | — |
| 205Rn | 205 | 119 | 204,991723 | — | 170 s | 5/2 | ⁻ | — |
| 206Rn | 206 | 120 | 205,990195 | — | 5.67 min | 0 | ⁺ | — |
| 207Rn | 207 | 121 | 206,990730 | — | 9.25 min | 5/2 | ⁻ | — |
| 208Rn | 208 | 122 | 207,989635 | — | 24.35 min | 0 | ⁺ | — |
| 209Rn | 209 | 123 | 208,990401 | — | 28.8 min | 5/2 | ⁻ | — |
| 210Rn | 210 | 124 | 209,989689 | — | 2.4 h | 0 | ⁺ | — |
| 211Rn | 211 | 125 | 210,990601 | — | 14.6 h | 1/2 | ⁻ | — |
| 212Rn | 212 | 126 | 211,990704 | — | 23.9 min | 0 | ⁺ | N magique |
| 213Rn | 213 | 127 | 212,993885 | — | 19.5 ms | 9/2 | ⁺ | — |
| 214Rn | 214 | 128 | 213,995363 | — | 259 ns | 0 | ⁺ | — |
| 215Rn | 215 | 129 | 214,998745 | — | 2.3 µs | 9/2 | ⁺ | — |
| 216Rn | 216 | 130 | 216,000272 | — | 29 µs | 0 | ⁺ | — |
| 217Rn | 217 | 131 | 217,003928 | — | 593 µs | 9/2 | ⁺ | — |
| 218Rn | 218 | 132 | 218,005601 | — | 33.75 ms | 0 | ⁺ | — |
| 219Rn | 219 | 133 | 219,009479 | — | 3.96 s | 5/2 | ⁺ | — |
| 220Rn | 220 | 134 | 220,011392 | — | 55.6 s | 0 | ⁺ | — |
| 221Rn | 221 | 135 | 221,015536 | — | 25.7 min | 7/2 | ⁺ | — |
| 222Rn | 222 | 136 | 222,017576 | — | 3.8215 j | 0 | ⁺ | — |
| 223Rn | 223 | 137 | 223,021889 | — | 24.3 min | 7/2 | — | |
| 224Rn | 224 | 138 | 224,024096 | — | 107 min | 0 | ⁺ | — |
| 225Rn | 225 | 139 | 225,028486 | — | 4.66 min | 7/2 | ⁻ | — |
| 226Rn | 226 | 140 | 226,030861 | — | 7.4 min | 0 | ⁺ | — |
| 227Rn | 227 | 141 | 227,035304 | — | 20.2 s | 3/2 | ⁺ | — |
| 228Rn | 228 | 142 | 228,037835 | — | 65 s | 0 | ⁺ | — |
| 229Rn | 229 | 143 | 229,042257 | — | 11.9 s | 5/2 | ⁺ | — |
| 230Rn | 230 | 144 | 230,045271 | — | — | 0 | ⁺ | — |
| 231Rn | 231 | 145 | 231,049973 | — | — | 1/2 | ⁺ | — |
Liseré coloré en première colonne : vert = stable, jaune = demi-vie > 1 an, orange > 1 jour, rouge < 1 jour.