Degenerate?

[Sophia Kangavari 1D]

Can someone please explain exactly what "degenerate" means and give an example? The textbook only says this on the topic: "An important feature of the hydrogen atom (but not for atoms with more than one electron) is that all the orbitals of a given shell have the same energy, regardless of the value of their orbital angular momentum (you can see from Eq. 2 that l does not appear in the expression for the energy). The orbitals of a shell in a hydrogen atom are said to be degenerate, which means that they all have the same energy. This degeneracy of orbitals with the same value of n but different values of l is true only of the hydrogen atom and one-electron ions such as He+ and Cu5+.
I feel like there's something I'm missing...
Thanks!

[Joshua Lee 3C]

Orbital degeneracy means that each orbital has the same energy level. For example, the 2px,2py, and 2pz orbitals are degenerate as they are all on the same energy level (2p). However, 2px and 2s would not be degenerate as they are different energy levels. Similarly 2px and 3px would not be degenerate as they are not on the same energy level. The reason that only one electron ions are degenerate is because if there is only one electron, then that electron can only occupy one orbital. If only one orbital is in use, then all the orbitals have to be the same energy level because there is only one.

[Arjun_Anumula_3E]

Thanks for the explanation. However I am still confused on how this would apply to atom like Helium. Even though it has multiple electrons, wouldn't the only available orbital be 1s? Because there are no other values of l in the first energy level right?

"This degeneracy of orbitals with the same value of n but different values of l is true only of the hydrogen atom and one-electron ions such as He+ and Cu5+". Why wouldn't this statement also apply to Helium

[305607822]

I think because He is a "hydrogen-like" atom.

[Lizzy Bulla 3K]

Degenerate means the states are at the same energy level. In MO theory, the 2px and 2py orbitals are degenerate. This is because on MO diagrams, they'll show on the same level.

[Alex Luong 3H]

It means all orbitals have the same energy.

[JafarriNocentelli 1G]

As previously mentioned, it means the orbitals are all equal in energy

[205903804]

Hello! I believe orbital degeneracy is when the orbitals have the same level of energy.