Benzene contains a special type of conjugation that exists throughout the entire ring structure and this greatly stabilizes it by lowering its energy. But what exactly is the quantity of energy by which this molecule is stabilized? How can we actually go about quantifying this stabilization energy? One way to do it is to compare the expected heat of hydrogenation of benzene to the actual experimental value. The heat of hydrogenation of cyclohexene is around -28.6 kcal/mol so this means that since benzene contains two more pi bonds than cyclohexene, the expected heat of hydrogenation should be around three times that amount, or -85.8 kcal/mol. However, experimental results tell us that the heat of hydrogenation is around -49.3 kcal/mol. This difference in energy between the expected value and the actual value is known as the delocalization energy. It is the energy difference as a result of the stabilizing effect of the conjugation that exists on benzene.