What is the product when an alkene is hydrogenated with H2 in the presence of Ni or Pt and heat?

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Multiple Choice

What is the product when an alkene is hydrogenated with H2 in the presence of Ni or Pt and heat?

Catalytic hydrogenation of an alkene adds hydrogen across the carbon–carbon double bond, converting it into a single bond and giving the corresponding alkane. The metal catalyst (Ni or Pt) helps by dissociating H2 into adsorbed hydrogen atoms and bringing the alkene and hydrogen together so both carbons of the former double bond receive one hydrogen atom (syn addition). Because the double bond is saturated, the product is a fully hydrogenated hydrocarbon, i.e., an alkane. The other options would require different reagents to introduce halogens or hydroxyl groups, or to preserve unsaturation; under these conditions, those pathways don’t occur.

Catalytic hydrogenation of an alkene adds hydrogen across the carbon–carbon double bond, converting it into a single bond and giving the corresponding alkane. The metal catalyst (Ni or Pt) helps by dissociating H2 into adsorbed hydrogen atoms and bringing the alkene and hydrogen together so both carbons of the former double bond receive one hydrogen atom (syn addition). Because the double bond is saturated, the product is a fully hydrogenated hydrocarbon, i.e., an alkane. The other options would require different reagents to introduce halogens or hydroxyl groups, or to preserve unsaturation; under these conditions, those pathways don’t occur.

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