Iodine vs Protactinium
| Property | I Iodine | Pa Protactinium |
|---|---|---|
| Atomic number | 53 | 91 |
| Symbol | I | Pa |
| Name | Iodine | Protactinium |
| Category | halogen | actinide |
| Standard Atomic Weight | 126.90447 u | 231.03588 u |
| Period | 5 | 7 |
| Group | 17 | N/A |
| Block | p | s |
| Phase at STP | solid | solid |
| Electron configuration | [Kr]5s24d105p5 | [Rn]7s25f26d1 |
| Oxidation states | [-1, 1, 2, 3, 4, 5, 6, 7] | [2, 3, 4, 5] |
| Electronegativity (Pauling) | 2.66 | 1.5 |
| Electron affinity | 3.059 eV | 0.123 eV |
| Density | 4930 kg/m³ | 1.537000e+4 kg/m³ |
| Melting point | 113.7 °C | 1571.85 °C |
| Boiling point | 184.4 °C | -273.15 °C |
| Discovery year | 1811 | 1913 |