NEET2017ChemistryAldehydes and KetonesActual
Consider the reactions: Identify A , X , Y and Z .
Options
- AA - Methoxyymethane, X - Ethanoic acid, Y - Acetate ion, Z - hydrazine.
- BA - Methoxymethane, X - Ethanol, Y - Ethanoic acid, Z - Semicarbazide.
- CA - Ethanal, X - Ethanol, Y - But-2-enal, Z - Semicarbazone.
- DA - Ethanol, X - Acetaldehyde, Y - Butanone, Z - Hydrazone.
Correct answer
C. A - Ethanal, X - Ethanol, Y - But-2-enal, Z - Semicarbazone.
Step-by-step solution
Since ' A ' gives positive silver mirror test therefore, it must be an aldehyde or α -Hydroxyketone. Reaction with semicarbazide indicates that A can be an aldehyde or ketone. Reaction with OH - i.e., aldol condensation (by assuming alkali to be dilute) indicates that A is aldehyde as aldol reaction of ketones is reversible and carried out in special apparatus. These indicate option ( iii ) .