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 ’ $C$ ‘.

(a) $CH _3 CH _2 CH=NNHCONH _2$

$(2002,3 M)$

(b) $H _3 C-\underset{CH _3}{C}=NNHCONH _2$

(c)

(d) $CH _3 CH _2 OH+NCONHNH _2$

Show Answer

Answer:

Correct Answer: 19. $(a)$

Solution:

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

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



NCERT Chapter Video Solution

Dual Pane