CHXII12:ALDEHYDES KETONES AND CARBOXYLIC ACIDS
323480
Which of the following organic compounds answers to both Iodoform test and Fehling's test?
1 Ethanal
2 Propanone
3 Ethanol
4 Methanal
Explanation:
Acetaldehyde (ethanal) gives red ppt. with Fehling solution.
\(\begin{array}{r}\mathrm{CH}_{3} \mathrm{CHO}+\underset{\text { Fehling solution }}{2 \mathrm{Cu}(\mathrm{OH})_{2}}+2 \mathrm{NaOH} \rightarrow \\\mathrm{CH}_{3} \mathrm{COONa}+\underset{\text { Red ppt. }}{\mathrm{Cu}_{2} \mathrm{O}}+3 \mathrm{H}_{2} \mathrm{O}\end{array}\)
Ethanal also gives yellow ppt. with an alkaline solution of iodine (Iodoform test).
\(\begin{aligned}& \mathrm{CH}_{3} \mathrm{CHO}+4 \mathrm{NaOH}+3 \mathrm{I}_{2} \rightarrow \\& \underset{\text { Yellow ppt. }}{\mathrm{CHI}_{3}}+\mathrm{HCOONa}+3 \mathrm{H}_{2} \mathrm{O}+3 \mathrm{NaI}\end{aligned}\)
