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Video transcript

in the video on solubility I draw little pictures of sodium and chloride ions when sodium chloride dissolves or disassociates into water this is sodium and this is chloride and my simple brain when I looked at it I said okay how should I draw these things I said well they're in the same period and sodium is a group one element it's alkali it's an alkali metal while chloride chlorine is a is a halogen so chlorine is going to have a smaller atomic radius and the logic there just to review from the atomic table trends is that they both have both of their valence electrons are in the third shell sodium only has 11 protons pulling in the center has 11 in the center and it has only one electron out there and it's in its valence shell so the attraction isn't as strong as the case of chloride which has 17 protons in the center and then so it will although it has more valence electrons it has seven of them oh is that six seven the set these protons are going to have a stronger attraction on them and so the if you just look at the trend in the periodic table you would expect the sodium neutral atom to be bigger than the chloride neutral atom because this guy has more protons pulling everything in and that's how I drew the ions in that video I said oh when I discipline the water I'll have a big sodium ion and a smaller chloride ion chlorine ion which is incorrect because think about and this was pointed out to me by one of the viewers and and they are correct and I should have realised this what happens when you ionize these things this guy will lose an electron right he gives the electron to this guy so his electron configuration is actually going to look a lot more like neons he's now going back he now will have no electrons in that third shell in the third energy state so now he's going to have an atomic radius that's actually much more similar to neons here right because he's only he's going to have filled up the second shell so actually the sodium ion this is completely incorrect the sodium ion is going to have an atomic radius not that different than neon actually it'll be even a little smaller than neon because it has the same electron configuration but it has one more proton so the sodium ion is actually going to be smaller because it gets rid of the electron in the third shell and the chloride the chlorine ion cation gained an electron so it's completely completed its third shell so here you have where the chlorine ion is going to be bigger so in that solubility video I should have actually switched the places between the sodium and the chlorine at least in size-wise and of course you know I showed how they disassociate in water and you know this would be attracted to the oxygen end of the water and you know the hydrogen ends and all that but although you can watch the solubility for that video for that it doesn't change the real take away from the video but I think this is a really interesting point that brings up that you when you when you ionize these neutral atoms it can significantly change especially significant change their relative atomic sizes anyway hopefully you found that interesting
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