Ground State vs. Excited State

[Rachel Kho Disc 2G]

I’m having some trouble understanding ground state electron configurations versus excited state electron configurations. When looking at the orbital diagram, how are you able to tell the difference between the two? What exactly goes into the orbital diagram of an excited state electron?

This concept is primarily part of question 1D.7 in the textbook.

[Halle Villalobos 3E]

Hi! I found this video on youtube that might help clarify things: https://www.youtube.com/watch?v=2VRTUuCnoxQ I hope this answered your question!

[Sana Nagori 2H]

Ground state configuration would be the configuration that you expect to see then following the rules that we learned about in class like Pauli's Exclusion Principle and Hunds rule. In an excited state, you'll see in electron in a higher energy level than expected. For example, Helium's ground state configuration is 1s2 but if it says 1s1 2s1 then you know that it is excited state.

[Gabby Magat 3F]

For the orbital diagrams (with the arrows showing the paired/parallel electrons), the ground state electron configuration of an atom would only be the configuration made by the Aufbau principle (and Pauli's/Hund's). Any other configuration (with different numbers of electrons occupying different orbitals) would be the excited state. I'm not sure about how to figure out 1D.7, though!

[SamanthaTolentino 3D]

The ground state configuration of an atom is when all principles such as Pauli's exclusion principle and hunds rule are obeyed. An atom is in an excited state when it does not obey the rules. For example for Oxygen, it would be in an excited state of the electrons in the p orbital were all paired rather than having a 2 unpaired electrons.

[Hannah Rim 2D]

A ground state electron configuration will look exactly the way you expect it to look if you wrote out the configuration as you see it on the periodic table. If you see a configuration that seems to "skip" any numbers while filling up the orbitals. then it is in the excited state.

[Jonathan Banh 1G]

Just in case, ground-state electron configuration refers to the typical electron configuration that would expect to see in atoms of elements while excited-state electron configuration refers to the electron configuration that is observed in them after additional energy is absorbed. Personally, I find it easier to think about excited-state electron configuration as abnormal ground-state electron configuration. This is because ground-state electron configuration is the lowest energy state for an element, however, when it is forcibly altered in some way, it signifies that the atom has increased in energy, meaning its electrons are excited, hence excited-state electron configuration. I believe the question you are referring to is 1E.7. In part (a), we can see that the electron configuration of carbon presented violates Hund's rule, as the electron did not fill up the other empty orbitals first with a parallel spin to the first. Since, this is not what is expected, we can conclude this is an excited-state electron configuration for carbon. On the other hand, if we look at part (d), where the electron configuration for oxygen is provided, we can see that it abides by both Pauli's exclusion principle and Hund's rule and thus is what we would typically expect to see. No alteration of electrons is present, so we can conclude that this is the ground-state electron configuration for oxygen.