हिन्दी में पढ़ेंHome › Elements › Radium
Radium (Ra)
Atomic number 88 · alkaline
| Atomic number | 88 |
|---|---|
| Atomic mass | 226.0 u |
| Molar mass | 226.0 g/mol |
| Category | alkaline |
| Group / period / block | 2 / 7 / s |
| Electron configuration | [Rn] 7s2 |
| Electrons per shell | 2, 8, 18, 32, 18, 8, 2 |
| Electronegativity (Pauling) | 0.9 |
| Atomic radius | 215.0 pm |
| Density | 5.0 g/cm³ |
| First ionisation energy | 5.2784 eV |
| Melting point | 969.15 K (696.00 °C) |
| Common oxidation states | +2 |
| Abundance in Earth's crust | 1e-06 ppm |
Uses
Historic glowing paint, cancer treatment
Discovery
1898, Pierre and Marie Curie