Chemical data for I - Iodine | PhysLink.com

Iodine

 Iodine 
I
Atomic Number: 53
Atomic Weight: 126.90447
Element Type: Halogen
Crystal Structure: Orthorhombic
Melting Point: 113.7°C = 236.66°F = 386.85 K
Boiling Point: 184.4°C = 363.92°F = 457.55 K
Critical Temp: 546.0°C = 1014.8°F = 819.15 K
Atomic Radius: 1.32 Å (Å = Angstrom = 10-10 m)
Covalent Radius: 1.33 Å
Electronegativity: 2.66

History

(Gr. iodes, violet) Discovered by Courtois in 1811, Iodine, a halogen, occurs sparinglyin the form of iodides in sea water from which it is assimilated by seaweeds, in Chileansaltpeter and nitrate-bearing earth, known as caliche in brines from old sea deposits, andin brackish waters from oil and salt wells.


Sources

Ultrapure iodine can be obtained from the reaction of potassium iodide with coppersulfate. Several other methods of isolating the element are known.