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Q.
Substance having ester linkage is:
BHUBHU 2003
Solution:
Bakelite : It is resin of formaldehyde $(HCHO) $ and phenol.
Polyethene : It is addition polymer of ethylene $\left( CH _{2}= CH _{2}\right)$. It has $CH _{2}- CH _{2}$ linkages.
PVC : It is polymer of vinyl chloride $\left( CH _{2}= CHCl \right) \text {. }$
Terylene : It is condensation polymer of terephthalic acid and ethylene glycol. It has ester linkages. These linkages are formed between acid and alcohol.