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53
I
126.90
Iodine
Halogens · Group 17 · Period 5
Atomic properties
| Atomic number | 53 |
|---|---|
| Symbol | I |
| Standard atomic weight | 126.90 |
| Classification | Halogens |
| Group | 17 |
| Period | 5 |
| Block | p-block |
| Electron configuration | [Kr] 4d10 5s2 5p5 |
| Electronegativity (Pauling) | 2.66 |
| Common oxidation states | +7, +5, +1, -1 |
Physical properties
| Phase at 20 °C | Solid |
|---|---|
| Density | 4.933 g/cm³ |
| Melting point | 113.7 °C |
| Boiling point | 184.3 °C |
| Discovered | 1811 |
| CAS number | — |