53 - Iodine diatomic nonmetal
Discovered by Bernard Courtois in 1811
Iodine 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.
H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
57-71 La-Lu Lanthanides
89-103 Ac-Lr Actinides
| Shell | Electrons | Orbitals |
|---|---|---|
| 1 | 2 | 2 in 1s |
| 2 | 8 | 2 in 2s + 6 in 2p |
| 3 | 18 | 2 in 3s + 6 in 3p + 10 in 3d |
| 4 | 18 | 2 in 4s + 6 in 4p + 10 in 4d |
| 5 | 7 | 2 in 5s + 5 in 5p |
lustrous metallic gray, violet as a gas Appearance
127 u Atomic Mass
1.4 Å Atomic Radius
457 K Boiling Point
17 Group
-1, 1, 3, 5, 7 Common Oxidation States
1.39 Å Covalent Radius
4.93 g/cm³ Density
295 kJ/mol Electron Affinity
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p5 Electron Configuration
[Kr] 4d10 5s2 5p5 Electron Configuration (semantic)
2.66 Electronegativity
53 Electrons
10.5 eV First Ionization Energy
-1, 5 ICSD Oxidation States
1008.4, 1845.9, 3180 kJ/mol Ionization Energies
387 K Melting Point
97 Mendeleev Number
5 Number of Shells
7 Electron Valency
74 Neutrons
53 Atomic Number
24 Number of Isotopes
-1, 1, 3, 5, 7 Oxidation States
5 Period
Solid Phase
53 Protons
2, 8, 18, 18, 7 Electron Shell Occupations