Steps to write Lewis dot structures

Writing a Lewis dot structure follows a fixed eight-step procedure. First, add up the TOTAL number of valence electrons contributed by every atom in the molecule (adjusting for any overall ionic charge — see steps 5 and 6). Second, sketch the molecule's skeletal (connectivity) structure, placing one shared electron pair — a single bond — between every pair of atoms that are directly bonded. Third, use up the remaining electrons by adding them as lone pairs so that every atom's octet (or duplet, for H) is completed as far as possible. Fourth, if any atom's octet is STILL incomplete after step 3, convert one or more of its single bonds into double or triple bonds (by moving a lone pair from a neighbouring atom into the bond) until every atom's octet is satisfied. Fifth, for an ANION, add one extra electron to the total for every unit of negative charge the ion carries. Sixth, for a CATION, subtract one electron from the total for every unit of positive charge. Seventh, in a polyatomic species, the LEAST electronegative atom is normally placed as the central atom — for example sulfur is central in $\text{SO}_4^{2-}$ and nitrogen is central in $\text{NO}_3^-$. Eighth, once the single-bond skel …