Which of the following statements about the polymerisation of ethylene to polyethylene is correct?
Answer
The process involves the formation of a free radical at the active centre.
The correct answer is The process involves the formation of a free radical at the active centre. — Thus option (B) correctly states the free‑radical mechanism.
Step-by-step solution
- Identify that the polymerisation of ethylene is an addition (chain-growth) reaction.
- Recall that chain-growth polymerisation proceeds via free‑radical, cationic or anionic active sites; ethylene polymerises by free radicals under typical conditions.
- Check each option: (A) describes condensation (incorrect), (C) suggests alternating double bonds (incorrect – polyethylene is saturated), (D) mentions removal of hydrogen (incorrect).
- Thus option (B) correctly states the free‑radical mechanism.
Common mistake: Choosing the condensation‑type option (A) instead of the free‑radical option
Concept tested: Addition polymerisation mechanism
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