53I126.9045
Iodine
Halogen
Solid at STP
Period 5Group 17Block PDiscovered 1811
[Kr]5s2 4d10 5p5
Iodine is a chemical element with symbol I and atomic number 53. The name is from Greek ἰοειδής ioeidēs, meaning violet or purple, due to the color of iodine vapor. Iodine and its compounds are primarily used in nutrition, and industrially in the production of acetic acid and certain polymers.
📖 Read more on Wikipedia →Atomic Properties
| Atomic Number | 53 |
| Atomic Mass | 126.9045 u |
| Electron Configuration | [Kr]5s2 4d10 5p5 |
| Oxidation States | +7, +5, +1, -1 |
| Electronegativity | 2.66 (Pauling) |
| Atomic Radius | 198 pm |
| Ionization Energy | 10.451 eV |
| Electron Affinity | 3.059 eV |
| Block | P |
Physical Properties
| Appearance | lustrous metallic gray, violet as a gas |
| Standard State | Solid |
| Melting Point | 386.85 K (113.7 °C) |
| Boiling Point | 457.55 K (184.4 °C) |
| Density | 4.93 g/cm³ |
| CPK Color | #940094 |
Classification
| Category | Halogen |
| Group Block | Halogen |
| Period | 5 |
| Group | 17 |
| Block | P |
Discovery
| Year Discovered | 1811 |
| Discovered By | Bernard Courtois |
| Electron Shells | 2, 8, 18, 18, 7 |