Alcohols and Ethers - Result Question 16

19. Compound ’ $A$ ’ (molecular formula $C _3 H _8 O$ ) is treated with acidified potassium dichromate to form a product ’ $B$ ’ (molecular formula $C _3 H _6 O$ ) ’ $B$ ’ forms a shining silver mirror on warming with ammoniacal silver nitrate. ’ $B$ ’ when treated with an aqueous solution of $H _2 NCONHNH _2$ and sodium acetate gives a product ’ $C$ ‘. Identify the structure of ’ $C$ ‘.

$(2002,3 M)$

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Answer:

Correct Answer: 19. $(a)$

Solution:

$A$ is an alcohol and its oxidation product gives Tollen’s test, i.e. $B$ must be an aldehyde $\left(CH _3 CH _2 CHO\right)$.

$ \begin{aligned} CH _3 CH _2 CHO+\underset{\text { semicarbazide }}{H _2 NHN-CO-} NH _2 & \\ CH _3 CH _2-CH & =N-NH-CONH _2 \end{aligned} $