A hydrocarbon A (C5H8) decolourises Br2/CCl4 and gives a white precipitate with ammoniacal AgNO3. Complete catalytic hydrogenation of A gives 2-methylbutane. A is

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A hydrocarbon A ( $C X_{5} H X_{8}$ ) decolourises $Br X_{2} / CCl X_{4}$ and gives a white precipitate with ammoniacal $AgNO X_{3}$ . Complete catalytic hydrogenation of A gives 2-methylbutane. A is

Apent-2-yne
Bpent-1-yne
C2-methylbuta-1,3-diene
D3-methylbut-1-yne

Answer: D

The silver test shows a terminal alkyne, and the product skeleton is branched (2-methylbutane). Pent-1-yne would give pentane and pent-2-yne is internal. Isoprene gives 2-methylbutane but has no acidic

\equiv C - H

. So A is

(CH X_{3}) X_{2} CH - C \equiv CH

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A hydrocarbon A (CX5​HX8​) decolourises BrX2​/CClX4​ and gives a white precipitate with ammoniacal AgNOX3​. Complete catalytic hydrogenation of A gives 2-methylbutane. A is

Answer: D

More questions on Distinguishing tests for functional groups

A hydrocarbon A ( $C X_{5} H X_{8}$ ) decolourises $Br X_{2} / CCl X_{4}$ and gives a white precipitate with ammoniacal $AgNO X_{3}$ . Complete catalytic hydrogenation of A gives 2-methylbutane. A is