Problem 21 - A Complete Resource Book in Chemistry for JEE Main

Question

PVC is formed by polymerization of (a) 1 -chloroethene (b) ethane (c) propene (d) 1 -chloropropane

Step-by-Step Solution

Answer

PVC is formed by polymerization of 1-chloroethene (option a).

Step 1: Understanding Polymerization

Polymerization is the process where monomer units are chemically bonded to form a polymer. In the case of Polyvinyl Chloride (PVC), a particular monomer is used.

Step 2: Identifying the Monomer for PVC

PVC is formed through the polymerization of the monomer vinyl chloride, which is chemically known as 1-chloroethene.

Step 3: Matching with Options

Among the given options, 1-chloroethene corresponds to option (a). This chemical structure matches the vinyl chloride needed for forming PVC.

Key Concepts

Polyvinyl Chloride (PVC)

Polyvinyl Chloride, commonly shortened to PVC, is one of the most widely used synthetic plastic polymers in the world. It is known for its durability, resistance to environmental degradation, and versatility of application in various industries. PVC is used in plumbing, electrical cable insulation, medical devices, and even clothing.
PVC is a polymer, meaning it is made from thousands of repeating units of a smaller chemical compound known as a monomer. The process of forming PVC involves the polymerization of these monomer units under specific conditions.

• **Durable**: Resists wear and tear.
• **Versatile**: Used in numerous applications.
• **Recyclable**: Can be remade into new products.

This plastic's properties make it invaluable across different sectors, offering both practical usage and ease of fabrication.

Monomer units

Monomers are the building blocks of polymers. A single monomer is like a unique piece of a puzzle, and polymerization is the process that connects these pieces together into a long chain, resulting in a polymer. Monomers can connect through chemical reactions, and the conditions under which polymerization occurs can affect the properties of the final polymer.
The type and structure of a monomer are critical, as each polymer's characteristics are directly linked to the monomer units used to create it. For PVC, the monomer used is vinyl chloride.

• **Basic unit**: Fundamental for forming polymers.
• **Versatile applications**: Different monomers create different polymers.
• **Connected chemically**: Bonding determines the properties and functions.

Understanding monomer units is important for predicting how a polymer will behave and be used in real-world applications.

1-chloroethene

1-chloroethene, also known as vinyl chloride, is the monomer used to create Polyvinyl Chloride (PVC). Its chemical structure is designated by a two-carbon compound with a chlorine atom attached to one of the carbons, which gives it unique properties.
The chemical formula for 1-chloroethene is C₂H₃Cl and its structure can be depicted as:\[CH_2=CHCl\]

• **Chemical formula**: C₂H₃Cl
• **Structure**: Contains a double bond and a chlorine atom.
• **Role in PVC**: Essential for creating the polymer's chains.

Vinyl chloride's specific structure facilitates the formation of strong, flexible, and durable PVC, which explains the material's widespread use.