Writing Lewis Structure

Steps 1.Count the total number of valence electrons a.Add one for each negative charge b.Subtract one for each positive charge 2.Write the skeletal structure a.Element with the least # of atoms or least electronegative goes in the center b.Connect bonded atoms with single bonds first

3.Complete an octet for all atoms remaining a.Exceptions: H, Al, B, Be 4.If there are not enough electrons, form double and triple bonds on the central atom as needed

Example 1: CF 4

Example 2: NH 3

Example 3: H 2 S

Example 4: NH 4 +

Example 5: PO 4 3-

Example 6: CO 2

Example 7: CO

Example 8: BCl 4

RESONANCE

Draw the Lewis Structure for O 3

Lewis Structure for O 3

Example 9: NO 3 −

Example 10: SO 3