The carbonate ion CO₃²⁻ has three equivalent resonance structures. All three C-O bonds are
- A
Double bonds
- B
Single bonds
- C
Triple bonds
- Dcheck_circle
Equivalent — average bond order ~ 4/3 (between single and double)
Explanation
Resonance delocalizes the double-bond character across all three C-O bonds; experimental bond lengths are equal and intermediate.