Iodine (I): Properties, Uses and Facts in 3D
Iodine is element 53 on the periodic table, a halogen, so it is a nonmetal. At room temperature it is a solid. Open it in the 3D Periodic Table to spin its tile, see its electron shells and read its story.
Explore in 3DIodine quick facts
| Atomic number | 53 |
|---|---|
| Symbol | I |
| Atomic mass | 126.904 |
| Category | Halogen |
| Group and period | Group 17, period 5 |
| Block | p-block |
| State at room temperature | Solid |
| Electron configuration | [Kr] 4d¹⁰ 5s² 5p⁵ |
| Electrons per shell | 2, 8, 18, 18, 7 |
| Discovered | 1811, Courtois |
What is iodine used for?
- Thyroid function (essential nutrient)
- Antiseptic (iodine solution)
- Contrast agent in CT scans
Interesting facts about iodine
- Iodine deficiency is the most common preventable cause of intellectual disability worldwide
- Iodine vapour is purple. Its name comes from the Greek for violet
- Adding iodine to table salt is one of the most cost-effective public health measures ever implemented
Iodine was discovered in 1811 by Courtois in France.
Where iodine sits on the periodic table
Iodine is in group 17, period 5. Tap any element to open its page.
Other halogens
Iodine questions
What is the atomic number of iodine?
Iodine has atomic number 53, so every iodine atom has 53 protons in its nucleus. Its symbol is I and its atomic mass is 126.904.
Is iodine a metal?
Iodine is a nonmetal. On the periodic table it is grouped as a halogen, found in group 17, period 5.
What is the electron configuration of iodine?
The electron configuration of iodine is [Kr] 4d¹⁰ 5s² 5p⁵. Its electrons sit in 5 shells: 2, 8, 18, 18, 7.
What is iodine used for?
Iodine is used for thyroid function (essential nutrient), antiseptic (iodine solution) and contrast agent in ct scans.
Who discovered iodine?
Iodine was discovered in 1811 by Courtois in France.
The 3D Periodic Table is made by Julian Neagu, a solo founder in London, as part of VisionVix Simulators. It is free to use in the browser on desktop and phone, with no sign-up.