Chapter 23, Problem 48A

a)

Interpretation Introduction

Interpretation: To write the structures and the expected products for the given reactions.

Concept Introduction: Esterification is a chemical reaction in which the alcohol is made to combine with the organic acid to form esters with the removal of the water molecule. This reaction takes place in the presence of a catalyst. A catalyst like ${\text{H}}_{\text{2}}{\text{SO}}_{\text{4}}$ in concentrated form is used in this reaction.

Answer to Problem 48A

  ${\text{CH}}_{\text{3}}{\text{COOH+CH}}_{\text{3}}\text{OH}\stackrel{{\text{H}}^{\text{+}}}{\to }{\text{CH}}_{\text{3}}{\text{COOCH}}_{\text{3}}+{\text{H}}_{\text{2}}\text{O}$

  

Explanation of Solution

In the given reaction carboxylic ${\text{CH}}_{\text{3}}\text{COOH}$ acid is made to react with the alcohol ${\text{CH}}_{\text{3}}\text{OH}$ in the presence of an acidic medium that resulted in the formation of an ester compound ${\text{CH}}_{\text{3}}{\text{COOCH}}_{\text{3}}$ with the removal of a water molecule.

b)

Interpretation Introduction

Interpretation: To write the structures and the expected products for the given reactions.

Concept introduction: The reaction is the hydrolysis of ester in the presence of an acid catalyst. The reaction in which water is used will be slow. The acid catalyst is used as a catalyst to increase the speed of the reaction. The ester is hydrolyzed to alcohol and carboxylic acid.

Answer to Problem 48A

  ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{COOCH}}_{\text{2}}{\text{CH}}_{\text{3}}+{\text{H}}_{\text{2}}\text{O}\stackrel{{\text{H}}^{\text{+}}}{\to }{\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{COOH+CH}}_{\text{3}}{\text{CH}}_{\text{2}}\text{OH}$

  

Explanation of Solution

In the given reaction, the ester ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}{\text{COOCH}}_{\text{2}}{\text{CH}}_{\text{3}}$ on reacting with water in the presence of a dilute acid catalyst which on hydrolysis will produce butyric acid ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}{\text{CH}}_{\text{2}}\text{COOH}$ and ethanol ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}\text{OH}$ .

c)

Interpretation Introduction

Interpretation: To characterize the reactions given as addition, esterification, substitution, polymerization, and oxidation reaction.

Concept Introduction: Oxidation reactions involve the transfer of elements between two elements. The oxidation number of an atom or an ion gets changed during the oxidation reaction. Oxidation is also referred to as the reaction of gaining oxygen.

Answer to Problem 48A

  ${\text{CH}}_{\text{3}}{\text{CH}}_{\text{2}}\text{OH}\underset{{\text{H}}^{\text{+}}}{\overset{{\text{K}}_{\text{2}}{\text{Cr}}_{\text{2}}{\text{O}}_{\text{7}}}{\to }}{\text{CH}}_{\text{3}}\text{CHO}$

  

Explanation of Solution

In the given reaction, alcohols are converted to aldehydes. The oxidation of alcohols in the presence of oxidizing reagents like ${\text{K}}_{\text{2}}{\text{Cr}}_{\text{2}}{\text{O}}_{\text{7}}$ in the presence of an acidic medium will produce aldehydes due to the gaining of oxygen.