The Lewis Structure

The Lewis structure of a molecule shows how the valence electrons are arranged among the atoms within a molecule.  Formation of a stable molecule requires that each atom in the molecule have enough valence electrons to achieve a noble gas electron configuration. Hydrogen requires 2 valence electrons while carbon and elements beyond require eight.  This is the basis for the octet rule, octet referring to eight valence electrons.

Lets look at some rules that can be used to correctly draw the Lewis structure for a molecule.