Rubidium vs Strontium
Side-by-side comparison of Rubidium (Rb, element 37) and Strontium (Sr, element 38) by atomic structure and physical properties.
| | |
|---|
| Atomic number | 37 | 38 |
|---|
| Symbol | Rb | Sr |
|---|
| Name | Rubidium | Strontium |
|---|
| Category | alkali-metal | alkaline-earth-metal |
|---|
| Standard Atomic Weight | 85.4678 u | 87.62 u |
|---|
| Period | 5 | 5 |
|---|
| Group | 1 | 2 |
|---|
| Block | s | s |
|---|
| Phase at STP | Solid | Solid |
|---|
| Electron configuration | [Kr]5s1 | [Kr]5s2 |
|---|
| Oxidation states | [-1, 1] | [1, 2] |
|---|
| Electronegativity (Pauling) | 0.82 | 0.95 |
|---|
| Electron affinity | 0.4859 eV | 0.052 eV |
|---|
| Density | 1530 kg/m³ | 2640 kg/m³ |
|---|
| Melting point | 39.31 °C | 776.85 °C |
|---|
| Boiling point | 687.85 °C | 1381.85 °C |
|---|
| Discovery year | 1861 | 1792 |
|---|
Key Differences
| Rb Rubidium | Sr Strontium |
|---|
| Standard Atomic Weight | 85.4678 u ↓ lower | 87.62 u ↑ higher |
|---|
| Density | 1530 kg/m³ ↓ lower | 2640 kg/m³ ↑ higher |
|---|
| Melting point | 39.31 °C ↓ lower | 776.85 °C ↑ higher |
|---|
| Boiling point | 687.85 °C ↓ lower | 1381.85 °C ↑ higher |
|---|
| Electronegativity (Pauling) | 0.82 ↓ lower | 0.95 ↑ higher |
|---|
| Electron affinity | 0.4859 eV ↑ higher | 0.052 eV ↓ lower |
|---|
| Group | 1 | 2 |
|---|
| Category | alkali-metal | alkaline-earth-metal |
|---|
| Electron configuration | [Kr]5s1 | [Kr]5s2 |
|---|
| Discovery year | 1861 | 1792 |
|---|