The following do not represent valid ground-state electron configurations for an atom either because they violate the Pauli exclusion principle or because orbitals are not filled in order of increasing energy. Indicate which of these two principles is violated in each example. (b) 3Xe46s3

Video transcript

Hello everyone in this video. We're seeing if this electron configuration here is breaking any of these three rules. Let's have a little refresher about what these three rules are talking about while the poly exclusion principle states that no two electrons can have the same set of quantum numbers. So I say no matching quantum numbers. All right. Next is the Hunts room. It says that each orbital of a sub shell must Singley be occupied with the electron before an orbital is doubly occupied. So one electron her little before being paired. And lastly the principle. But this state is that electrons are to fill lower energy orbital's before higher energy orbital's. So say lower orbital first. Before high energy or higher orbital. We were just talking about the energy regarding the higher and lower states. Okay, so taking a closer look at the given electron configuration. That's gonna go ahead and expand this out. So I'll go ahead and rewrite this the A. R. And then three d. 10 four P six And five s. 2. So let's closely evaluate this. We can see that if you're reading this specific part here and ignoring this noble guess That this electron configuration actually skipped the four s orbital. Before you see here this is the five of us. But we forgot that for us. Where is that located at? And because so save me skipped four S orbital. This is very important because we can take this and re read what rules we have and seeing which one that applies to. So no matching quantum numbers that didn't apply for orbital one electron pra orbital before being paired. There's nothing about being paired and not paired But for skipping the four s orbital, the lower orbital first before higher orbital. This is what applies here the alphabetic principle because we're skipping the four S orbital and we see that we have a five S. So the answer for this question is going to be seek the principle because we're filling up the higher orbital before we get to the lower orbital and that's incorrect. We need to do this one first before the five.