Chapter 2, Problem 83CP

(a)

Interpretation Introduction

Interpretation:

Resonance structure of anion 2 and cation 3 of the given compound has to be drawn.

Concept Introduction:

Curved arrows are necessary in drawing the resonance structure.

Curved arrows has a head indicating that the electrons are coming and tail indicating that the electrons are going.

The two rules in drawing the resonance structure is,

• Breaking of single bond is not allowed.
• Never exceed an octet for second row elements.

When a single Lewis structure does not represent a structure adequately, the true structure is the intermediate between the two or more structure referred to as resonance structure.

(b)

Interpretation Introduction

Interpretation:

Reason for why $\text{C-C}$ bond length in compound 1 varies greatly but bond length in ions of 2 and 3 are similar has to be explained.

Concept Introduction:

Bond length: Bond distance or bond length is the average distance between nuclei of two bonded atoms in a molecule. It is a transferable property of a bond between atoms of fixed types

Single bond ($1.54A^0$) are longer than double bond ($1.34A^0$) and triple bond($1.20A^0$)

(c)

Interpretation Introduction

Interpretation:

Reason for why the intermolecular hydrogen bonding in structure 3 diminishes in comparison to the structure 1 has to be explained.

Concept Introduction:

Hydrogen bonding is a type of dipole-dipole interaction of molecules when the hydrogen is bonded to strong electronegative atom (F, O, N, etc) in the molecules.

Intramolecular hydrogen bonding is the hydrogen bonding with a molecule.