Question

The correct stability order of the above given resonating structures is:

• A. $\left(IV\right)>\left(I\right)>\left(III\right)>\left(II\right)$
• B. $\left(II\right)>\left(IV\right)>\left(I\right)>\left(III\right)$
• C. $\left(III\right)>\left(II\right)>\left(IV\right)>\left(I\right)$
• D. $\left(I\right)>\left(IV\right)>\left(III\right)>\left(II\right)$

Answer 1

The correct option is D $\left(I\right)>\left(IV\right)>\left(III\right)>\left(II\right)$

Structure I: It is the most stable resonating structure because it is neutral and has two double bonds.
Structure IV: It has a complete octet on each atom. There are two pi bonds in the structure.
Structure II and III: Both of these have incomplete octets at '$C$' atom bearing positive charge, but in the IIIrd structure, the negative charge is present on the more electro-negative atom, i.e., oxygen.
So, the order is $\left(I\right)>\left(II\right)>\left(III\right)>\left(IV\right)$.