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How does resonance make the two oxygen-oxygen bonds in ozone equivalent?

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Diagram showing four types of crystal bonding: ionic bonding with sodium and chlorine ions, covalent bonding with carbon atoms sharing electrons, metallic bonding with iron ions surrounded by free electrons, and molecular bonding with hydrogen molecules held by weak electrical attraction. — chemical bonding Different types of bonding in crystals.

In chemistry, the ambiguity regarding the location of double bonds in the ozone (O₃) molecule is resolved through a quantum mechanical phenomenon known as resonance.12

While individual Lewis structures may suggest distinct single and double bonds, the actual structure of the ozone molecule is a resonance hybrid—a blend of these contributing structures. Resonance acts as a blending process that spreads the double-bond character evenly across the participating atoms.132

As a result, the two oxygen-oxygen bonds in ozone are rendered equivalent, with each bond possessing a mixture of single-bond and double-bond character. This equivalence is reflected in the observed length and strength of the bonds, which are intermediate between those of a pure single bond and a pure double bond.12