Name the reagents to distinguish acetone and acetaldehyde by lodoform test.
Answers
Answer:
Acetaldehyde acts as reducing agent and reduce (i) Fehlings solution (ii) Tollen's regent, and (iii) Schiff reagent.
Acetaldehyde itself is oxidised to acetic acid.
Acetone is not oxidised with these reagents as Acetone has no H atom directly attached to carbonyl carbon atom.
(i) Fehlings solution
CH
3
−CHO+2Cu
2+
+5OH
−
Δ
CH
3
−COO
−
+Cu
2
O↓+3H
2
O
CH
3
−C(O)−CH
3
+2Cu
2+
+5OH
−
Δ
no reaction
(ii) Tollen's regent
CH
3
−CHO+2[Ag(NH
3
)
2
]
+
+3OH
−
Δ
CH
3
−COO
−
+2Ag↓+2H
2
O+4NH
3
CH
3
−C(O)−CH
3
+2[Ag(NH
3
)
2
]
+
+3OH
−
Δ
no reaction
(iii) Schiff reagent.
Acetaldehyde +schiff reagent → magenta colour is restored.
Acetone +schiff reagent → magenta colour is not restored
Explanation: