Chapter 1, Problem 21PP

Interpretation Introduction

Interpretation: Curved arrows showing electron movement are to be drawn and the formula for the structure that would contribute most to the hybrid is to be designated.

Concept introduction:

Resonating structures are structures that have more than one equivalent Lewis structure for the same molecule or ion.

According to the convention, these structures are connected by double-headed arrows ($\stackrel{}{\leftrightarrow }$).

Movement of electrons (whether bonding or lone pair) is indicated by curved arrows.

The rules for writing the resonance structures are:

Resonance structures have existence in paper only, they are not real structures.

While writing the resonance structures, movement of either double bonded electrons or lone pair of electrons are shown.

All structures should be correct Lewis structures.

The energy of any contributing structure is higher than the energy of the resonance hybrid.

For equivalent resonating structures, the resonance stabilization is large.

The rules for deciding which resonance structure contributes more to the hybrid than other are:

The more stable structure is that which has more covalent bonds.

Stability of resonating structures is decreased by charge separation.

The structures that contain complete valence shell are more stable.

Stability of resonating structures is increased as the electrons in valence shell completed.