1. A Review of General Chemistry
Summary
Video duration:
2mRelated Videos
Skip to main content
The ground state electron configuration is just the distribution of electrons, 1 s, 2 s, 2 p, 3 s, and so on, within orbitals using the Aufbau principle. Aufbau means build up in German. And the Aufbau principle itself says, starting from 1 s, electrons fill lower energy orbitals before moving to higher energy orbitals. When we talk about the condensed electron configuration, this is just a quicker way of writing it out. Here we'd say we start at the last noble gas before the desired element. If we look at our periodic table, we break it up into different blocks. We have our s block, our p block, our d block, and our f block. Organic chemistry is really concerned with our non metals. So for the most part, you're not gonna deal with d blocks and f blocks. And if we take a look here at this periodic table, we start out with hydrogen here, which is 1 s 1. Helium would be 1 s 2, because we're dealing with our 2nd electron. We get to our 3rd electron. The 1 s is filled, so we move on to 2 s, 2 s 1. This will be 1 s22s2, which is why we go to 2p1 over here. Continuing, this will be 3 s, so this will be 1 s 2, 2 s 2, 2p63 s 1, eventually getting us over here, where this would end with 3p1. Looking at this pattern, let's see what we can do in terms of this example. We'd say write the ground state and condense electron configurations for the following element, phosphorus. Here is phosphorus right here. I tell us its atomic number z is 15, so it has 15 electrons. So following the pattern that we just saw, in this spot here that I circled, this would be 1 s 2, 2 s 2, 2 p 6, 3 s23p1. And all we gotta do is count to phosphorus. So that would be for the ground state, it'd be 1 s 2, 2 s 2, 2 p 6, 3 s 2, 3 p 3, because it's 3p1, 3p2, 3p3. If you add up all the electrons that we have here, it would add up to 15, which is equal to the atomic number. Now the last noble gas we pass before we get to phosphorus is neon. So neon is the element right here. So it's condensed electron configuration. We'd start out with the noble gas, neon, and then we'd have 3 s 23p3. So this will represent our ground state and condensed electron configuration for the Phosphorus atom.
00:24
