Problem 109 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the following \begin{tabular}{ll} \hline Column-I & Column-II \\ \hline (a) Starch & (p) Polymer of amino acid \\ (b) Nylon - 6 & (q) Polymer of \(\alpha-\mathrm{D}-\) Glucose \\ (c) Protein & (r) Polyamide \\ (d) Natural rubber & (s) Isoprene \\ & (t) Caprolactum \end{tabular}

Step-by-Step Solution

Answer

(a) - (q), (b) - (r), (c) - (p), (d) - (s)

Step 1: Match Starch with Column-II

Starch is a carbohydrate composed of a large number of b1-D-glucose units. Therefore, it matches with option (q) "Polymer of \(\alpha-\mathrm{D}-\) Glucose".

Step 2: Match Nylon-6 with Column-II

Nylon-6 is a type of synthetic polymer known as a polyamide. It matches with option (r) "Polyamide". Although caprolactam (t) is a precursor to Nylon-6, the polymer is specifically a polyamide.

Step 3: Match Protein with Column-II

Proteins are natural polymers made up of amino acids. Therefore, they match with option (p) "Polymer of amino acid".

Step 4: Match Natural Rubber with Column-II

Natural rubber consists of polymerized isoprene units, which makes it match with option (s) "Isoprene".

Key Concepts

Understanding Starch in Polymer Chemistry

Starch is a fascinating example of a biopolymer. It is one of the primary energy storage carbohydrates found in plants. Made up of numerous glucose units, this complex carbohydrate is a crucial part of the human diet.
Starch is composed of two types of molecules: amylose and amylopectin. Amylose is primarily a linear chain of glucose units, whereas amylopectin is a branched chain. This structure helps starch store energy and makes it digestible in the human body.

• Amylose: Linear chains.
• Amylopectin: Branched chains.

Starch acts as a polymer of glucose, precisely known as b-glucose. In the context of polymer chemistry, starch serves as a model for understanding how natural polymers function and how they can break down into glucose, providing energy.

Nylon-6 in the World of Synthetic Polymers

Nylon-6 represents an interesting aspect of synthetic polymers. It is part of a larger family known as polyamides, which are revered for their strength and elasticity. Nylon-6 is synthesized from caprolactam, a lactam (cyclic amide) that undergoes a ring-opening polymerization process.
As a polyamide, Nylon-6 incorporates amide linkages in its backbone. These linkages contribute to its toughness and ability to withstand significant wear and tear.

• Synthetic polymer.
• Derived from caprolactam.
• Contains amide linkages.

Nylon-6 is widely used in the textile and industrial sectors for producing items such as ropes, fibers, and tire reinforcements. It exemplifies the important role of synthetic polymers in modern material science and industry.

Proteins: Natural Polymers of Life

Proteins are undoubtedly one of the most critical polymers in the realm of natural compounds. They are large, complex molecules essential for numerous biological functions, including catalyzing reactions, providing cellular structure, and acting as transporters, among others.
Proteins are polymers made up of amino acid monomers linked by peptide bonds resulting in a polypeptide chain. These chains fold into specific three-dimensional structures that determine the protein's function and properties.

• Composed of amino acids.
• Linked by peptide bonds.
• Fold into specific structures.

Understanding proteins helps researchers develop medical treatments, advance nutritional sciences, and explore the fundamentals of life on a molecular level.

The Chemistry of Natural Rubber

Natural rubber is a well-known example of a natural polymer. It arises from the latex sap of rubber trees and comprises polymerized isoprene units, technically known as cis-1,4-polyisoprene. This compound is responsible for the unique properties of natural rubber, such as its flexibility, elasticity, and toughness.
The polymerization of isoprene in natural rubber is a natural chemical process that confers high tensile strength and elongation.

• Derived from rubber tree latex.
• Composed of polymerized isoprene.
• Offers flexibility and elasticity.

Due to its impressive qualities, natural rubber is used in a variety of products, including tires, footwear, and adhesives. It demonstrates the power of polymer chemistry in transforming raw, natural materials into invaluable resources for daily life.