Which compound has the most exothermic (most negative) heat of hydrogenation?

Question

Quizplus · Accepted Answer

The heat of hydrogenation measures the stability of an alkene through the addition of hydrogen. The more negative the value, the more stable the alkene. Looking at the structures given, it can be observed that compound II has two double bonds in a cis configuration, which is the most unstable geometry for a double bond due to steric hindrance. Additionally, compound II has an electron-withdrawing nitro group, making it more reactive towards hydrogenation. Therefore, compound II will have the most negative heat of hydrogenation, making choice B the correct answer.

Which Compound Has the Most Exothermic (Most Negative) Heat of Hydrogenation