Drawing Lewis dot structure for covalently bonded molecules

​​​General rules:

1 Attach all atoms with one bond (known as the sigma bond).  Make the molecule as symmetrical as possible.  Never attach H to more than l other atoms

2.  Draw 8 electrons around each atom (Except H)

3.  Count the number of electrons drawn.  Record

4.  Using the periodic table, count only the valence electrons each atom actually has and find the sum

       If the group has a net negative charge, add one extra electron for each negative

       If the group has a net positive charge, subtract one for each positive

5.  Find the difference between what was drawn and what it possesses.  For each 2 extra, you will add a 2nd bond (called the pi bond) while crossing off 2 "dots" from one atom and 2 "dots" from the adjacent atom.  These dots remember represent electrons

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