Lewis structures

Follow these steps when drawing a Lewis structure of a molecule:

  1. Arrange bonded atoms symmetrically around the central atom.
  2. Count the total number of valence electrons (including an ion’s charge).
  3. Place a bonding pair of electrons between the central atom and each atom surrounding it.
  4. Complete the octets of surrounding atoms with lone pairs, and, if the total number of electrons is not yet reached, add lone pairs to the central atom.
  5. If the central atom doesn’t have an octet, move pairs from bonded atoms to form double bonds or triple bonds.
  6. Draw the final Lewis structure. If it is a polyatomic ion, enclose it in square brackets and indicate the charge with a superscript.