Iodine

Halogen · 126.9045 u · group 17, period 5

←Te Xe→

Iodine · I

Identity

Atomic number53

SymbolI

CategoryHalogen

Standard stateSolid

Group · Period · Block17 · 5 · p

Electron configuration[Kr]5s2 4d10 5p5

Atomic

Atomic mass126.9045 u

Atomic radius198 pm

Protons / Neutrons / Electrons53 / 74 / 53

Shells (e⁻ per shell)2, 8, 18, 18, 7

Chemical

Electronegativity (Pauling)2.66

Ionization energy10.451 eV

Electron affinity3.059 eV

Oxidation states+7, +5, +1, -1

Physical

Melting point386.9 K · 113.7 °C

Boiling point457.6 K · 184.4 °C

Density4.93 g/cm³

History

Year discovered1811

CPK color

#940094

State at room temp (25 °C)

solid

Position

Molecules with I

6 in library

I₂

CH₃I

F₅I

F₇I

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