But-2-yne is treated with H2 over Lindlar catalyst. The product is

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NEET levelSingle correct optionDifficulty 1 of 3hc114

But-2-yne is treated with $H X_{2}$ over Lindlar catalyst. The product is

Abutane
Bcis-but-2-ene
Ctrans-but-2-ene
Dbut-1-ene

Answer: B

Lindlar catalyst (poisoned Pd) stops at the alkene stage and delivers both hydrogens to the same face (syn addition), so an internal alkyne gives the cis (Z) alkene.

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But-2-yne is treated with HX2​ over Lindlar catalyst. The product is

Answer: B

More questions on Alkynes: acidity, preparation and reactions

But-2-yne is treated with $H X_{2}$ over Lindlar catalyst. The product is