Do electrons go to even lower ground states after exothermic reactions?

Question

I am a bit confused about what happens to the energy levels during an exothermic reaction.

I understand that during an exothermic reaction, the energy of the electrons decreases.

Is the potential energy of electrons related to the energy level diagram, shown below?

So if the potential energy decreases, does that mean the ground state for the new molecules formed will be different from the old molecules?

Related: https://chemistry.stackexchange.com/questions/114347/what-is-meant-by-electrons-moving-to-lower-potential-energy/114350?noredirect=1#comment214923_114350 — Karsten, Apr 27 '19 at 03:48

Poutnik · Answer 1 · 2019-04-27T07:54:36.473

4

Yes, electron energy levels are like that, especially for single atoms.

Yes, forming molecular bonds creates different electron energy levels, with exothermic reactions leading to chemical bonds with lower ground levels then the reagents had.

Note that by an electron ground energy level is meant the minimal energy of energy levels unocuppied by other electrons.

As an electron is forbidden by quantum rules to be in the same quantum state as any other electron within an atom or molecule.

Thermal, photon or collision excitations may keep part of electrons in excited state.

Much more info you can get reading about

on Wikipedia.

edited Apr 27 '19 at 07:54

answered Apr 27 '19 at 00:38

Poutnik

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So when the exothermic reaction finishes, will the electrons end up at the ground energy level? – Mason Riley Apr 27 '19 at 03:31
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Usually yes, even if sometimes they can even temporarily stay excited. – Poutnik Apr 27 '19 at 04:18
AFAIK, reaction of NO with O3 produces excited NO2, that later emits a photon. – Poutnik Apr 27 '19 at 07:07

Do electrons go to even lower ground states after exothermic reactions?

1 Answers1