Why is 02 a double bond?
It has to be for each oxygen atom to satisfy the octet rule.
The diatomic oxygen molecule contains a total of 12 valence electrons, spread amongst two atoms. Each oxygen atom needs to have 8 surrounding it, so it can satisfy the octet rule. As a result, it needs to share two pair with the other oxygen atom. To avoid having a double bond, it would need 14.
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