Hydrogenation energy
The energy that is released during the addition of elemental hydrogen (H 2 ) to chemical compounds is referred to as hydrogenation energy or hydrogenation enthalpy . A common example is the hydrogenation of unsaturated hydrocarbons to saturated hydrocarbons.
The hydrogenation energy is calculated from the difference between the enthalpies of formation of the hydrogenated and the unhydrogenated compound.
For alkenes , it is approximately 120 kJ / mol per double bond . This rough guideline decreases with the number and length of linked alkyl groups . The hydrogenation energy is thus a value for estimating the stability of a compound.