Beryllium vs Potassium
| Property | Be Beryllium | K Potassium |
|---|---|---|
| Atomic number | 4 | 19 |
| Symbol | Be | K |
| Name | Beryllium | Potassium |
| Category | alkaline-earth-metal | alkali-metal |
| Standard Atomic Weight | 9.012183 u | 39.0983 u |
| Period | 2 | 4 |
| Group | 2 | 1 |
| Block | s | s |
| Phase at STP | solid | solid |
| Electron configuration | [He]2s2 | [Ar]4s1 |
| Oxidation states | [0, 1, 2] | [-1, 1] |
| Electronegativity (Pauling) | 1.57 | 0.82 |
| Electron affinity | -0.52 eV | 0.5014 eV |
| Density | 1850 kg/m³ | 890 kg/m³ |
| Melting point | 1286.85 °C | 63.38 °C |
| Boiling point | 2470.85 °C | 758.85 °C |
| Discovery year | 1797 | 1807 |