Here's why:
* Ozone's structure: Ozone has a central oxygen atom bonded to two other oxygen atoms.
* Resonance: The double bond in ozone is actually delocalized, meaning it's not fixed between any two specific oxygen atoms. The electrons are spread out over all three oxygen atoms. This is represented by drawing two resonance structures.
The resonance structures for ozone look like this:
[Image: Two structures of O3, one with a double bond between the left and middle oxygen atoms, and the other with a double bond between the middle and right oxygen atoms. The single bonds are shown as lines, and the double bond as two lines.]
Important Note: These are just representations. The actual ozone molecule is a hybrid of these two structures, with the double bond character spread out over all three oxygen atoms.
