Addition of Hydrogen to Alkenes

Addition of hydrogen to unsaturated hydrocarbons takes place in the presence of a catalyst like Ni, Pt or Pd.

Alkenes (and alkynes) can be converted to alkanes by the addition of hydrogen in the presence of a catalyst like nickel, platinum or palladium.

This reaction is also called hydrogenation and is used to prepare vegetable ghee from edible oils (by converting unsaturated fats to saturated ones)