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Kostas Ampatzis

Reactivity order in hydrogenation reaction of but-2-yne and butene isomers

Chris Pohl  Follow

Correct reason for 2nd question is heat of hydrogenation is inversely proportional to the stability of the compound. And (D) is most stable due to conjugation.

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Ifeanyi Dominic  Follow
Good answer, I know a classic example of this is to compare the heat of hydrogenation of hydrogen with that of cyclohexene. The heat of hydrogenation of benzene is much less than three times that cyclohexene.More
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Blair Blakely  Follow

Monosubstituted alkene is more reactive than disubstituted because directly attached alkyl groups stabilize the system. Therefore 1 butene is more reactive.

Cis is more reactive than trans because Cis compounds are unstable. As they have similar groups on same side, it results in stearic crowding.

Thirdly, conjugated dienes are very stable beacuse they are resonance stabilized.

Thus order will be1 butene will be most reactive, then Cis, then trans and then 1,3 butadiene..

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