Guide for Drawing Lewis Structures 1. Determine the total number of valence electrons for the molecule. To do this, look at which group the element is in on the periodic table. o if you have an ion, add or subtract electrons as necessary to the above total. MBO
2. Draw initial connectivity by placing the least electronegative atom (not considering hydrogen) in the molecule at the center. Next, draw individual lines (bonds) to connect atoms (each line contains 2 electrons) to complete the octets around all the atoms bonded to the central atom.
3. Place leftover electrons on the central atom, even if doing so results in more than an octet of electrons around the atom.
4. If there are not enough electrons to give the central atom an octet, try multiple bonds (double covalent or even triple covalent).​