Hydrogenation of alkenes using H2 and Ni yields which product?

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Multiple Choice

Hydrogenation of alkenes using H2 and Ni yields which product?

Hydrogenation with hydrogen gas over a nickel catalyst is a reduction of the carbon–carbon double bond. The pi bond is broken and two hydrogen atoms are added across the bond, converting the alkene into a saturated alkane. This adds one hydrogen to each carbon of the double bond, giving a single C–C bond and two new C–H bonds, so you get a saturated hydrocarbon like ethane from ethene, propane from propene, and so on. No oxygen-containing groups are introduced in this process, so alcohols, ethers, or carboxylic acids aren’t formed under these conditions—the reaction simply saturates the molecule. The nickel catalyst helps break H–H and transfers hydrogen to the carbons, often with syn addition across the original double bond.

Hydrogenation with hydrogen gas over a nickel catalyst is a reduction of the carbon–carbon double bond. The pi bond is broken and two hydrogen atoms are added across the bond, converting the alkene into a saturated alkane. This adds one hydrogen to each carbon of the double bond, giving a single C–C bond and two new C–H bonds, so you get a saturated hydrocarbon like ethane from ethene, propane from propene, and so on. No oxygen-containing groups are introduced in this process, so alcohols, ethers, or carboxylic acids aren’t formed under these conditions—the reaction simply saturates the molecule. The nickel catalyst helps break H–H and transfers hydrogen to the carbons, often with syn addition across the original double bond.

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