Chapter 1, Problem 1.80P

Interpretation Introduction

(a)

Interpretation:

All valid resonance contributors for the given ion are to be drawn using curved arrows to indicate which pairs of electrons are being shifted.

Concept introduction:

Resonance structure exists in species for which there are two or more valid Lewis structures. Resonance structures are imaginary; true species is represented by the resonance hybrid. Resonance structures differ only in the placement of their valence electrons, not their atoms. For a species, each valid Lewis structure is called a “resonance structure” or a “resonance contributor.” Resonance structures are drawn using curved arrows. The arrow points to the center of an existing bond to represent the formation of a new double/triple bond. A resonance structure can be drawn if a lone pair of electrons on an atom is adjacent with multiple bonds or an incomplete octet on an atom is adjacent to multiple bonds or there is a ring of alternating single and double bonds.

Interpretation Introduction

(b)

Interpretation:

Resonance hybrid for the given anion is to be drawn.

Concept introduction:

For a species, each valid Lewis structure is called a “resonance structure” or a “resonance contributor.” A resonance hybrid is a weighted average of all resonance contributors. A partial bond is represented in a resonance hybrid by a dashed line connecting the two atoms.