Chapter 19.3, Problem 19.3PP

Interpretation Introduction

(a)

Interpretation:

The structure of wax formed from stearic acid ( ${\text{CH}}_{\text{3}}{\left({\text{CH}}_{\text{2}}\right)}_{16}\text{COOH}$ ) and ${\text{CH}}_{\text{3}}{\left({\text{CH}}_{\text{2}}\right)}_{\text{9}}\text{OH}$ should be drawn.

Concept Introduction:

Waxes are good example of hydrolysable lipids which are composed of fatty acid and higher alcohols. They have ester functional group which is formed between $\text{–COOH and –OH}$ functional group of the fatty acid and alcohols respectively. The general reaction of wax formation from fatty acid and higher alcohols can be written as:

  ${\text{R-CH}}_{\text{2}}{\text{-COOH + HO-CH}}_{\text{2}}\text{-R }\stackrel{}{\to }{\text{R-CH}}_{\text{2}}{\text{-COO-CH}}_{\text{2}}{\text{-R + H}}_{\text{2}}\text{O}$

Interpretation Introduction

(b)

Interpretation:

The structure of wax formed from stearic acid ( ${\text{CH}}_{\text{3}}{\left({\text{CH}}_{\text{2}}\right)}_{16}\text{COOH}$ ) and ${\text{CH}}_{\text{3}}{\left({\text{CH}}_{\text{2}}\right)}_{\text{11}}\text{OH}$ should be drawn.

Concept Introduction:

Waxes are good example of hydrolysable lipids which are composed of fatty acid and higher alcohols. They have ester functional group, which is formed between $\text{–COOH and –OH}$ functional group of the fatty acid and alcohols respectively. The general reaction of wax formation from fatty acid and higher alcohols can be written as:

  ${\text{R-CH}}_{\text{2}}{\text{-COOH + HO-CH}}_{\text{2}}\text{-R }\stackrel{}{\to }{\text{R-CH}}_{\text{2}}{\text{-COO-CH}}_{\text{2}}{\text{-R + H}}_{\text{2}}\text{O}$

Interpretation Introduction

(c)

Interpretation:

The structure of wax formed from stearic acid ( ${\text{CH}}_{\text{3}}{\left({\text{CH}}_{\text{2}}\right)}_{16}\text{COOH}$ ) and ${\text{CH}}_{\text{3}}{\left({\text{CH}}_{\text{2}}\right)}_{\text{29}}\text{OH}$ should be drawn.

Concept Introduction:

Lipids are biomolecules that are involved in different biochemical reactions. They are special types of organic molecules which can only be identified with the help of their physical properties, not by the presence of any certain functional group.

In general, lipids contain a large number of C-C and C-H bonds with few polar functional groups such as $\text{–OH, -SH}$ , etc. Waxes are good example of hydrolysable lipids which are composed of fatty acid and higher alcohols. They have ester functional group which is formed between $\text{–COOH and –OH}$ functional group of the fatty acid and alcohols respectively. The general reaction of wax formation from fatty acid and higher alcohols can be written as:

  ${\text{R-CH}}_{\text{2}}{\text{-COOH + HO-CH}}_{\text{2}}\text{-R }\stackrel{}{\to }{\text{R-CH}}_{\text{2}}{\text{-COO-CH}}_{\text{2}}{\text{-R + H}}_{\text{2}}\text{O}$