The Octet Rule for Some Diatomic Gases

Recall that some elemental gases— hydrogen, nitrogen, oxygen, and fluorine—do not consist of individual atoms, but of diatomic molecules of H2, N2, O2, and F2, respectively. This can be e)q)lained by the tendencies of these elements to attain a noble gas outer electron configuration. The bonds in molecules of F2 are shown by the following  

It can be seen that the F2 molecule is held together by a single covalent bond consisting of 2 shared electrons. As shown by the circles around them, each atom in the molecules has 8 outer electrons, some of them shared. These 8 electrons constitute an octet of outer electrons. Such an octet is possessed by the neon atom, which is the noble gas nearest to F in the periodic table. 

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