Chemistry - Polymer Question with Solution | TestHub

Question Explanation: to identify number of copolymers and carbohydrates which show mutarotation. Concept: This question is based on copolymers and mutarotation. Solution : A copolymer is made from two (or more) different monomers. In the given polymer list: * Nylon-6,6 is made from hexamethylenediamine + adipic acid, making it a copolymer. * Buna-N (NBR) - butadiene + acrylonitrile → copolymer. * Dacron (PET) - ethylene glycol + terephthalic acid → copolymer. * Buna-S (SBR) - styrene + butadiene → copolymer. * Teflon (PTFE) - Polymer of tetrafluoroethylene (a single monomer) → homopolymer. * PHBV (poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) → copolymer.

So $X=5$.

Except for sucrose, all given carbohydrates can exhibit mutarotation because they possess a hemiacetal or hemiketal linkage:

* $\alpha$-D-Glucopyranose and $\beta$-D-Glucopyranose → The bond at C-1 (anomeric carbon) is a hemiacetal linkage → mutarotation.

* $\alpha$-D-Fructofuranose and $\beta$-D-Fructofuranose → At the anomeric carbon (C-2 in fructose), there is a hemiketal linkage (often grouped under hemiacetal linkages) → mutarotation. * Lactose → has one free hemiacetal linkage → mutarotation.

* Sucrose → Both anomeric carbons are involved in the glycosidic bond → no free hemiacetal → does not show mutarotation.

* In maltose, the second glucose unit still has a free anomeric carbon (C1) in hemiacetal form → mutarotation.

Thus$Y=6$.

$\frac{Y}{X}=\frac{6}{5}=1.2$