53 · I
Iodine
Obtained by Courtois in 1811.
Identity
- Atomic number
- 53
- Symbol
- I
- Canonical name
- Iodine
- Category
- halogen
- Group
- 17
- Period
- 5
- Block
- p
Properties
These quantities come from the Periodic Table JSON compilation. They have not yet been checked, one by one, against CIAAW atomic weights or NIST measurements. A value marked estimated is not a measurement.
- Atomic mass
- 126.904473 u
- Electron configuration
- [Kr] 4d10 5s2 5p5
- Electrons per shell
- 2, 8, 18, 18, 7
- Standard state
- solid
- Density
- 4.933 g/cm³
- Melting point
- 386.85 K
- Boiling point
- 457.4 K
- Electronegativity
- 2.66 Pauling
- First ionization energy
- 1,008.4 kJ/mol
- Electron affinity
- 295.1531 kJ/mol
Notable isotopes
This summary is not an inventory of every isotope.
- I-127 · 100 % · stable
History
Violet vapors from kelp ash
Discovery · confirmed · 1811
Courtois obtains iodine by treating seaweed ash.
Etymology
- Theme
- color
- Language
- grec
- Root
- iodes
- Meaning
- violet
Scientists
Places and institutions
- Paris — historical setting : France — present country : France
See also
Sources
- IUPAC, Periodic Table of the Elements
- Bowserinator, Periodic Table JSON. Compilation secondaire d’où viennent les grandeurs physiques importées (masse, densité, températures, énergies). Elles ne sont pas revérifiées une à une auprès du NIST ou de la CIAAW.
- John Emsley, Nature’s Building Blocks: An A–Z Guide to the Elements