Among the following ethers, which one will produce methyl alcohol on treatment with hot concentrated HI?

• ${\mathrm{CH}}_3-{\mathrm{CH}}_2-{\mathrm{CH}}_2-{\mathrm{CH}}_2-\mathrm{O}-{\mathrm{CH}}_3$

• ${\mathrm{CH}}_3-{\mathrm{CH}}_2-\underset{\underset{{\mathrm{CH}}_3}{|}}{\mathrm{CH}}-\mathrm{O}-{\mathrm{CH}}_3$

• ${\mathrm{CH}}_3-\mathrm{C}\left({\mathrm{C}}_3{\mathrm{H}}_6\right)-\mathrm{O}-{\mathrm{CH}}_3$

• ${\mathrm{CH}}_3-\underset{\underset{{\mathrm{CH}}_3}{|}}{\mathrm{CH}}-{\mathrm{CH}}_2-\mathrm{O}-{\mathrm{CH}}_3$

Nylon is an example of

• polyster

• polysaccharide

• polyamide

• polythene

43.

Which is the monomer of neoprene in the following?

• ${\mathrm{CH}}_2=\mathrm{CH}=\mathrm{C}\equiv \mathrm{CH}$

• ${\mathrm{CH}}_2=\mathrm{C}\left({\mathrm{CH}}_3\right)-\mathrm{CH}={\mathrm{CH}}_2$

• ${\mathrm{CH}}_2=\mathrm{C}\left(\mathrm{Cl}\right)-\mathrm{CH}={\mathrm{CH}}_2$

• ${\mathrm{CH}}_2=\mathrm{CH}-\mathrm{CH}={\mathrm{CH}}_2$

In the reaction,

                     A is

• HgSO₄ /H₂SO₄

• Cu₂Cl₂

• H₃PO₂ and H₂O

• H⁺ /H₂O

The order of stability of the following tatutomeric compound is

• I> II> III

• III > II> I

• II> I> III

• II > III> I