Question

Which reaction of polymerization proceeds step-wise?

(a) Addition reaction

(b) Condensation reaction

(c) Substitution reaction

(d) None of the mentioned

The question was posed to me during an interview.

This intriguing question originated from Chemistry of Polymerization Reaction topic in chapter Principles of Polymer Chemistry of Unit Processes

Answer 1

Right answer is (b) Condensation reaction

Easy explanation: The polymer formation in condensation polymerization proceeds stepwise, the various intermediates, dimer, trimer, etc., existing as stable molecules until the next reaction step. Small molecules, usually water, are split off at each step of the reaction.