P orbitals

[Nina Gautam 1K]

When electrons are filling up the p-orbitals, is it implicit that 2px gets occupied before 2py and that 2py gets occupied before 2pz (in that order) before a second electron occupies 2px? I understand Hund's rule that electrons will fill orbitals that are empty before pairing with another one, but in class it seemed like 2px was always filled before 2py, and then 2pz was the last orbital axis to be filled. Why is that? Why would 2py not be filled before 2px?

[Chris Pleman 3E]

The first three electrons in the P orbital will all have a positive spin, and will occupy the Px, then Py, then Pz, orbital. Then the next three will all have negative spins, and will fill in that order. When filling orbitals (usually) we go from left to right with a positive spin first, and then once you've reached the end, you start back at the beginning and fill left to right with negative spins.

[StephanieDoan3B]

All three orbitals have the same energy, and the electron will fill any of them first. We designate that px is filled first, then py, and pz because of convention.

[Diane Bui 2J]

Dr. Lavelle also explained how electrons with the same spin in the same subshell will occupy different orbitals due to electron repulsion. The electrons are more stable if they are in different orbitals.

[Wenjie Dong 2E]

All three orbitals have the same energy, and the electron will fill any of them first. We designate that px is filled first, then py, and pz because of convention.

I agree. So there will be a second electron on any of the orbit only if px, py, and pz are all filled with one already.