i) Two monomers Hexamethylenediamine [H₂N-(CH₂)₆-NH₂] and adipic acid [HOOC-(CH₂)₄-COOH] combined to form the polymer and a water molecule is removed in this process. Hydrogen(H) is removed from both sides of Hexamethylenediamine and OH group is removed from both sides of adipic acid to give a water molecule.

ii) The monomer is OC-(CH₂)₅-NH known as Caprolactam. The cyclic structure of the monomer changes to linear to form the polymer, as shown below:

(iii) The monomer is Tetrafluroethene (CF₂= CF₂), the double bond breaks to form the polymeric chain.