From the compounds given below, number of compounds which give positive Fehling's test is
Benzaldehyde, Acetaldehyde, Acetone, Acetophenone,Methanal, 4-nitrobenzaldehyde, cyclohexane carbaldehyde.

Question

From the compounds given below, number of compounds which give positive Fehling's test is Benzaldehyde, Acetaldehyde, Acetone, Acetophenone,Methanal, 4-nitrobenzaldehyde, cyclohexane carbaldehyde.

TestHub · Accepted Answer

In Fehling’s solution, the reaction between copper(II) ions and aliphatic aldehyde is represented as;

$RCHO + 2 {Cu}^{2 +} + 5 {OH}^{-} \to {RCOO}^{-} + {Cu}_{2} O + 3 H_{2} O$

Hence ,Acetaldehyde $({CH}_{3} CHO),$ Methanal $(HCHO)$ , and cyclohexane carbaldehyde

compounds gives positive Fehling's test.

Hence, the answer is $3$ .

Chemistry - Carbonyl compounds Question with Solution | TestHub

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