Energy and Quantum Numbers

[MedGrl@2022]

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I just want to make sure that I understand quantum numbers correctly

n=shell... the higher the shell number the higher the energy of the electron

l=subshell... in general the higher the subshell the higher the energy level (or no?)

m(l)=orbital... is there any relation with energy and orbital?

m(s)=spin... electrons spin number... usually electrons will fill all the orbitals before they start pairing... could some energy cause two electrons to share an orbital and leave an orbital empty?

I appreciate you helping me clarify things!

 

[milski]

You've got it.

Some additional info:

n - also called a principal quantum number. The energy is proportional to -1/n² - it increases as n goes up but in smaller and smaller increments, i.e. the difference between n=1 and n=2 is much larger than the difference between n=5 and n=6. n corresponds to the number in the 1s 2s 2p etc. designations.

l - can be between 0 and n-1. Energy is higher for higher l and the shape of the electron cloud depends on it. l=0 is s, l=1 is p, l=2 is d, etc.

m_l - range is from -l to l, the energies are the same (at least for MCAT purposes).

m_s - having two electrons in the same orbital is energetically expensive, I cannot think of any exceptions here. There are exceptions in the opposite direction though - Cr for example has [Ar]4s¹3d⁵ configuration with one more electron in the 5d subshell instead of two in the 4s. There are more exceptions in the heavier transition metals but I doubt that you'll need to memorize any of them for the MCAT.