Iodine
| Isotope | Atomic mass (Da) | Isotopic abundance (amount fraction) |
|---|---|---|
| 127I | 126.904 47(3) | 1 |
Iodine is a monoisotopic element and its atomic weight is determined solely by its isotope127I. The Commission last revised the standard atomic weight of iodine in 1985 based on the latest Atomic Mass Evaluation by IUPAP.
129I has been measured in terrestrial samples that have been exposed to cosmic radiation, and in materials that contain fallout fromnuclear explosions. These measurements can be used for geochronological and environmental studies,but they also confirm the low abundance of129I in nature, and its insignificance with respect to theatomic weight of iodine.
© IUPAC 2003
CIAAW
Iodine
Ar(I) = 126.904 47(3) since 1985
The name derives from the Greekiodes for "violet" because of its violet vapours. Iodine was discovered inseaweed by the French chemist Bernard Courtois in 1811, and named by the French chemist Louis-Joseph Gay-Lussac, when he proved it was an element in 1814.
