Which of the following compounds will give Fehling's solution test?

(A) $CH_3CHO$
(B) $C_6H_5CHO$
(C) $CH_3CH_2CHO$
(D) $HCHO$

(A), (C) and (D) only

The correct answer is Option (2) → (A), (C) and (D) only

Core Concept

Fehling’s solution gives a positive test with aliphatic aldehydes but not with aromatic aldehydes.

Explanation

Option A: CH₃CHO (Acetaldehyde)

This is an aliphatic aldehyde. It reduces Fehling’s solution to form red precipitate of Cu₂O.

Option B: C₆H₅CHO (Benzaldehyde)

This is an aromatic aldehyde. Due to resonance stabilization of –CHO group with benzene ring, it does not reduce Fehling’s solution.

Option C: CH₃CH₂CHO (Propanal)

This is also an aliphatic aldehyde. Hence, it gives positive Fehling’s test.

Option D: HCHO (Formaldehyde)

Formaldehyde is the simplest aliphatic aldehyde. It readily reduces Fehling’s solution.