Question

decide whether each row is a set of resonance structures for a single molecule and select \yes\ or
o\ in the last column. structures resonance structures? yes no yes no yes no yes no

Explanation:

Step1: Recall resonance - structure criteria

Resonance structures have the same connectivity of atoms and differ only in the distribution of electrons.

Step2: Analyze first - row structures

The first - row structures have different formal charges and electron - pair distributions but the same atom connectivity, so they are resonance structures.

Step3: Analyze second - row structures

The second - row structures have different atom connectivities (the first has a single bond between N and C, the second has a double bond), so they are not resonance structures.

Step4: Analyze third - row structures

The third - row structures have different atom connectivities (the position of the double bond is different in a way that cannot be explained by electron delocalization), so they are not resonance structures.

Step5: Analyze fourth - row structures

The fourth - row structures have the same atom connectivity and differ only in the distribution of electrons and formal charges, so they are resonance structures.

Answer:

1. yes
2. no
3. no
4. yes