Learn about Advanced Placement Chemistry, Atomic Theory 7, in this comprehensive video by bannanaiscool.
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Rob Lederer: Electron configurations for potassium and ion that helps also to understand, how these elements can ionize or become ions and how many electrons they would like to use electron configurations can help us to determine that watch potassium if you go through the periodic table is 1s2, 2s2, 2p6, 3s2, 3p6, 4s1 by the way you need a really good book or chart to some to show you what those orbital's look like S-orbital's are spherical and P orbital's are double low to orbital's G-orbital's are lower than weird and stuff like that how we look at those diagrams. I'm not going to draw I'm not terrible artist. So look at this potassium has this is the electron configuration its got electrons and equals one, two and three and link one at any phosphorus any phosphorus outside of all those other orbital's the electron at any phosphorus is further away from the nucleus. Its trying to look and be attracted to a nucleus of 19 protons but that electron is so shield and by all the other electrons that are very beneath it that we say that it is very effectively screened so what has an effective nuclear charge placed on that electron that is very small, if you know what I mean that's called the effective nuclear charges generally abbreviated Z with an EFF afterwards the Zeff. So this outer most electron doesn't feel the nucleus very much and so therefore it's relatively not as an easy but relatively desire to be able to plug it away then all the other electrons vary beneath it because it can feel the nucleus very well. So potassium doesn't mind loosing that one electron to get a positive one charge and on the periodic table it's an alkaline middle with the positive one charge, oh! ion is element 26, so here its electron configuration all the way to 3D6, now you are going to see why did you writing the 3D after 4S because that's the kind of way it occurs in the periodic table but you can write it like that, what are the outer most electrons however, well at any phosphor thy are the outer most electrons, so these electrons here you don't really touch them to ionize ion to pull away electrons from ion to make it a cation we put away the outer most electrons first with the other once that have the lower Zeff effective nuclear charge, Hey! That means then we could take away both of ions out most electrons relatively well and leave it with the two positive charge does an ion have a two positive charge. Yeah, of course that it also has a three positive 3D6, remember that a 3D you could have 5 orbital's, so we put boxes for each of the orbital's are sub orbital's and electron here, abbreviated s2, that we would -- one electron, two electrons, three electrons, four electrons, five electrons, six electrons. Two electrons in a space finding for that close that small space those electrons hide each other so for this electron we are able to say, Hey! I don't like it here, I mean there they also got their own rule and I don't I'm leaving. Its relatively easy to be able to take away this electron to take away one of the 3D electrons and leave it with 1s2, 2s2, 2p6, 3s2, 3p6, go on and 3D5 it looses three electrons relatively easy, guess what ion most popularly has a three positive charge because of this Oh! beautiful. Three important trends: First ionization energy, electron affinity and atomic radius. All of that sets us p to talk about three important trends on the periodic table, First one, first ionization energy known, ionization energy is how much energy is required to remove the outer most electron the first ionization energy from a gas these element its after to be heat up to a gas, how can -- how much energy does it take to pull when the first electron, well for Sodium remember it doesn't require that much because its outer most electron 3s1, so its out there away from the other electrons that are in closer to the 1s and 2s is called the core electrons and N equals 3 just a little bit outside easier to pluck of that electro. Now what's the