(i) Draw structures of the following derivatives

(a) Cyanohydrin of cyclobutanone

(b) Hemiacetal of ethanal

(ii) Write a major product(s) in the following

(a) ${\mathrm{CH}}_3-\mathrm{CH}=\mathrm{CH}-{\mathrm{CH}}_2-\mathrm{CN} \underset{\left(\mathrm{II}\right) {\mathrm{H}}_3{\mathrm{O}}^{+}}{\overset{\left(\mathrm{I}\right) \mathrm{DIBAL}-\mathrm{H}}{\to }}$

(b) ${\mathrm{CH}}_3-{\mathrm{CH}}_2-\mathrm{OH}\stackrel{{\mathrm{CrO}}_3}{\to }$

(iii) How can you distinguish between propanal and propanone?

OR

(i) Identify compound ‘A’ . Its molecular formula is ${\mathrm{C}}_2{\mathrm{H}}_4{\mathrm{O}}_2$ and gives brisk effervescence with ${\mathrm{NaHCO}}_3.$
(ii) Identify the major products X andY of reaction

(iii) Identify C of the following sequence of reactions