Terylerte is a condensation polymer of ethylene glycol and

dimethyl terephthalate

The answer is 3. dimethyl terephthalate. I apologize for the mistake.

Terylene is a condensation polymer of ethylene glycol and dimethyl terephthalate. Dimethyl terephthalate is a monomer that is made up of two ethylene glycol molecules and one phthalic acid molecule. The monomers react to form a polymer with an ester linkage. The condensation reaction produces water as a byproduct.

Here is the reaction for the condensation polymerization of ethylene glycol and dimethyl terephthalate to form terylene:

 \(n HO-CH_2-CH_2-OH + n C_6H_4(COOCH_3)_2 \longrightarrow [-OC(CH_2)_2CO-O-C_6H_4-CO-]_n + nH_2O\)

The product of the reaction is a long, chain-like molecule with ester linkages alternating along the chain. This molecule is called terylene.

Benzoic acid, phthalic acid, and salicylic acid are not used to make terylene.