9 posts • Page 1 of 1
According to Pauli Exclusion Principle, when two electrons do occupy one orbit, their spins must be paired. Electrons have parallel spins when they occupy different orbitals and must not be paired unless all of the orbitals have at least 1 electron in each.
When simply drawing out the configurations once all the oribtals have atleast one electron( at this point they are all parallel to one another) then when more electrons are added, the electrons in the same orbital begin to get paired. All of the orbitals must be filled by at least one electron before getting paired.
When you are filling out an orbital, know that each orbital must have one electron before the electrons are paired. This is because electrons prefer to be in different orbitals due to their negative charge that repels other electrons. So for example, if four electrons are in the p orbital there would only be one set of paired electrons. This is because there are three orbital so the first three electrons would occupy a different orbital and then the fourth one would be paired.
The easiest way to do this is to draw out the orbitals. For example, p has three orbitals that can fit six electrons. If you are in the p orbital draw out three lines. Now say you have four electrons in the p orbital, first draw one electron on each line all spinning upwards. The fourth electron will then pair up with one of the electrons spinning upwards, but it will spin down. Paired electrons always spin in opposite directions. When drawing the initial electrons in an orbital before they get paired, always draw them spinning upwards. Make sure to draw the electrons individually in their own orbital(Px,Py,Pz) before pairing them up as due to charges electrons will naturally avoid being paired up if possible.
aphung1G wrote:Does Hund's rule apply to the Pauli Exclusion Principle?
This is a bit of a strange question to ask. Hund's Rule describes the order in which electrons fill a subshell and is composed of two main statements: every orbital in a subshell must be singly occupied before any are doubly occupied, and all electrons in singly occupied orbitals must have the same spin (parallel). The Pauli Exclusion Principle states that no two electrons can have the exact same set of four quantum numbers, essentially that there cannot be two electrons in the same orbital with the same spin. I'm not sure you would say that one "applies" to the other as they describe somewhat different things. I hope that was able to clear things up a bit!
Who is online
Users browsing this forum: No registered users and 3 guests