Iodine is one of seven elements that usually form as diatomic molecules. These other "diatomics" are [tex]O_2, H_2, F_2, Br_2, N_2, [/tex] and [tex]Cl_2[/tex]. They typically bond to themselves.
Iodine has seven valence electrons. Using valence shell electron pair repulsion (VSEPR) theory, we can predict the Lewis dot structure for [tex]I_2[/tex]. We see there are fourteen electrons, and we can make a covalent bond, leaving three lone pairs on each atom. The bond replaces two electrons, so the number of electrons shared is two.
