Question

Natural rubber is a polymer of ________ while synthetic rubber neoprene is formed by polymerization of ________.

• A. 1,3-butadiene; acrylonitrile
• B. 2-chloro-1,3-butadiene; 1,3-butadiene
• C. 2-methyl-1,3-butadiene; 2-chloro-1,3-butadiene
• D. Acrylonitrile; 2-methyl-1,3-butadiene

Hint:

Natural rubber is polyisoprene (2-methyl-1,3-butadiene), while synthetic rubber neoprene is made from chloroprene (2-chloro-1,3-butadiene).

Answer 1

The Correct Option is C

Step 1: Understand the composition of natural rubber.
Natural rubber is a polymer of isoprene, which is chemically known as 2-methyl-1,3-butadiene. The polymerization of isoprene produces polyisoprene, which is the principal component of natural rubber.
Step 2: Understand what synthetic rubber neoprene is.
Neoprene is a type of synthetic rubber formed by the polymerization of chloroprene, which is chemically called 2-chloro-1,3-butadiene. This polymer is used for making hoses, gaskets, and wetsuits due to its high resistance to oil, heat, and weathering.
Step 3: Match the correct monomers.
Natural rubber → monomer = 2-methyl-1,3-butadiene (isoprene)
Neoprene → monomer = 2-chloro-1,3-butadiene (chloroprene)
Step 4: Analyze the options.
Option (1): Incorrect — Natural rubber is not made from 1,3-butadiene.
Option (2): Incorrect — This reverses the monomers of natural and synthetic rubber.
Option (3): Correct — Matches both monomers accurately.
Option (4): Incorrect — Acrylonitrile is used in other polymers like nitrile rubber, not natural rubber.