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I am having trouble relating stability with energy released. For example, I am looking at a statement regarding Benzene that says, since delocalised electron model of Benzene is more stable than the kekule model that has three double bonds, it gives out less energy than the kekule model upon reaction.

I am trying to relate this stability back to my learning of electron stability on different shells. The closer to the nucleus an electron is, the more stable it is, the more energy is released to remove it.

Why is the idea of stability completely different here?

Adnan Niloy
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    Energy is not released when you remove an electron or break a bond. –  Apr 30 '19 at 17:30
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    It takes energy to break a bond or to remove an electron from an atom, not release energy. If you correct that part in your statements, the rest will be consistent. – Karsten Apr 30 '19 at 17:32
  • I am sorry, I deleted the bond-related statements. – Adnan Niloy Apr 30 '19 at 17:36
  • Now what is your question, really? Both examples essentially say: "has more energy = less stable". – Ivan Neretin Apr 30 '19 at 18:21
  • "The closer to the nucleus an electron is, the more stable it is, the more energy is released to remove it. " This is the problem, energy is required to remove an electron from an atom. Try correcting this and see if it helps your logic. – Withnail Apr 30 '19 at 19:14
  • duplicate of https://chemistry.stackexchange.com/questions/108726/why-total-heat-of-hydrogenation-of-1-3-cyclohexadiene-is-more-than-that-of-benze – user55119 May 01 '19 at 01:10

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I think that your question revolves around the evidence that is normally given in organic texts around the stability of aromatic compounds such as benzene. enter image description here

chemguide.co.uk

The idea here is that addition reactions with benzene (such as hydrogenation) that involve bond formation that is stronger than the pi bonds that are broken are less exothermic than similar reactions with hypothetical cyclic alkenes such as cyclohexatriene. The implication is that there is some stabilization of benzene beyond what is expected from simple alkenes.

This is the main basis for the theory of aromaticity in molecules that obey the rules (planar, cyclic and having 2n + 2 pi electrons). If you wish to learn more about why benzene is more stable than expected, see this great question: Delocalised electrons and stability of benzene

There is no conflict with the understanding of electrons in lower potential energy orbitals being more stable. It is an extension of the same idea, just using molecular orbitals rather than atomic orbitals.

Withnail
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