Iodine (I)

From Wikipedia, the free encyclopediaIodine 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.

Iodine in the periodic table

SymbolI
Atomic number53
Group17
Period5
Blockp
Element categoryNonmetal

Physical properties

Phase at STPSolid
Density4.933 g/cm3
Atomic weight126.904 u
Melting point386.85 K
113.7 °C
236.66 °F
Boiling point457.4 K
184.25 °C
363.65 °F

Atomära egenskaper

Electronegativity (Pauling Scale)2.66
Electron affinity295.153 kJ/mol
Ionization energies
11008.4 kJ/mol
2 1845.9 kJ/mol
3 3180 kJ/mol

Electron configuration

Electron configuration1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p5
Electrons per shell2, 8, 18, 18, 7

History

Discovered1811
Discovered byBernard Courtois