Account for the following :
(i) `CH_(3)CHO` is more reactive than `CH_(3)COCH_3` towards reaction with `HCN`.
(ii) Carboxylic acid is a stronger acid then phenol .
(b) Wrtie the chemical equations to illuustrate the following reaction :
(i) Wolff-Kishner reduction
(ii) Aldol condensation
(iii) Cannizzaro reaction

Explanation

(a) (i) `CH_(3)COCH_(3)` is sterically hindered then `CH_(3)CHO` due to the the presence of alky1 group
on both sides of the carbony I carbon, marking them less reactive towards uncleophilic
attack because both methy I groups have elctron releasing tendency due to - I effect
These alky1 groups make ketone less reactive by donating electron to carbong 1 group
There fore,acetaldhyde is more reactive towards reaction with HCN.
(ii) Carboxylic acids are acidic due to resonance stabilisation of carboxylate anion and in
Phenols, acidic character is present due to resonance stabilisation of phenoxide anion.
Carboxylic acids are more acidic than phenols because the negative charge in
carboxylate O-atoms in carboxylate anion compared to one in phenxide ion . In the resonance structures of carboxylate anion, the negative charge is present on the O-atoms, while in
resonance of Phenoxide ion, negative charge is present on the
electropositive carbon atom, which leads to less stability of phenoxide ion than carboxylate anion.
(b) (i) Wolff-Kishner Reduction
(b) (i)
(ii) Aldol condensation
.