Now a structural formula shows how atoms in a compound are connected or bonded to one another. Now it's the same as a Lewis structure, except we do not show lone pairs. So if we took a look here at this structure, if we wanted to draw the Lewis formula, we'd remember that the oxygen has 2 lone pairs on it.
When it comes to our structural formula, we don't need to show the presence of those lone pairs on oxygen because we're more concerned on the bonds that are being created between our different atoms. We don't care about non-bonding electrons, which is typical with a Lewis dot structure, right?
So just remember both of these are showing how atoms are connected to one another or bonded to one another. But Lewis does a little bit more by showing us our non-bonding electrons or lone pairs. Structural formulas don't really care about that.