Complete each hydrogenation reaction. b.

Hydrogenation is a chemical reaction that involves the addition of hydrogen (H2) to an unsaturated compound, typically an alkene or alkyne, resulting in the formation of a saturated compound. This process is commonly used in organic chemistry to convert double or triple bonds into single bonds, thereby increasing the hydrogen content of the molecule.

Alkenes are hydrocarbons that contain at least one carbon-carbon double bond, while alkynes contain at least one carbon-carbon triple bond. These unsaturated hydrocarbons are more reactive than their saturated counterparts (alkanes) due to the presence of these multiple bonds, making them key targets for hydrogenation reactions to produce alkanes.

Hydrogenation reactions often require a catalyst to proceed efficiently, typically a metal such as palladium, platinum, or nickel. These catalysts facilitate the breaking of the H-H bond in molecular hydrogen and help to align the reactants for effective bonding, thus lowering the activation energy and increasing the reaction rate.