Chapter 22, Problem 22.60SP

(1)

Interpretation Introduction

Interpretation:

The most acidic hydrogens in the given compounds are to be indicated.

Concept introduction:

The substances that produce hydrogen ions (${\text{H}}^{\text{+}}$) on dissociation are known as acids. The substances that produce hydroxide ions (${\text{OH}}^{-}$) on dissociation are known as bases. The concept of acids and bases was expanded by Johannes Bronsted and Thomas Lowry in the early twentieth century.

According to the definition of Bronsted and Lowry, acids are the substances that donate protons whereas bases are the substances that accept protons.

Answer to Problem 22.60SP

The most acidic hydrogens in the given compounds are shown in Figure 1.

Explanation of Solution

In a molecule, different types of protons are present. However, when acting as acids, only the most acidic proton participates in the acid-base reaction. The protons of functional groups are most acidic in nature as they are easily available for donation.

Acidic hydrogen is defined as that hydrogen which is attached to more electronegative atoms like oxygen and fluorine. The compound (f) does not contain any acidic hydrogen atom in the given compounds.

The most acidic hydrogens in the given compounds are shown below.

Figure 1

(2)

Interpretation Introduction

Interpretation:

The structures of important resonance contributors of the anions of the given compounds are to be drawn.

Concept introduction:

The delocalization of electrons due to presence of lone pair and double bond is called resonating structure. The structure is more stable if the resonating structures are more.

Answer to Problem 22.60SP

The structures of important resonance contributors of the anions of the given compounds are shown below.

Explanation of Solution

The formation of carbanion occurs when acidic hydrogen is removed from a compound. The important resonance contributors of the anions that results from the removal of most acidic hydrogen are shown below.

(a)

Figure 2

(b)

Figure 3

(c)

Figure 4

(d)

Figure 5

(e)

Figure 6

(f)

The given compound is shown below.

Figure 7

The given compound does not contain any acidic hydrogen atom. Therefore, it does not show resonance structures.

(g)

Figure 8

(h)

Figure 9