Q.Write the name of the monomer unit(s) of Dacron and mention one use of it. (1+1)

Terylene (Dacron/PET) is a condensation polymer formed from a diol and a diacid, joined by repeating ester (–COO–) linkages — the defining feature of a polyester.

Terylene is manufactured by the condensation polymerisation of ethylene glycol (a diol) and terephthalic acid (a dicarboxylic acid) in the presence of a catalyst, with the two monomers repeatedly condensing (losing water) to form ester bonds along the chain:

$n\ HOCH_2CH_2OH + n\ HOOC-C_6H_4-COOH \rightarrow [-OCH_2CH_2OOC-C_6H_4-CO-]_n + 2n\ H_2O$

This repeating –COO– (ester) linkage classifies Terylene as a polyester.

…