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Electron Configuration of Calcium Ca Lesson

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Hi welcome back to moose in chemistry this is electronic configuration of calcium ca now calcium is the 20th element of the periodic table so we’re going to write a 20 for our atomic number calcium’s amu or mass number is 40 okay so now if it has an atomic number of 20 that means it has 20 protons and since calcium is electrically neutral it would have to have

20 electrons what about the number of neutrons well we looked at amu minus protons equals the number of neutrons okay so that would be 40 minus 20 would give me 20 neutrons purdy snarly eh so we’re going to put a 20 there but before we do the electron configuration we have to look at a couple of things s subshell could hold two electrons e sub shells can hold

Six electrons these subshells can hold ten electrons and the f sub shell can hold fourteen electrons we’re also going to use the diagonal rule right here and what we’re gonna do is we’ll start the top of this red arrow and we’re gonna work our way down until we run out of electrons following the errors so let’s go ahead and do the electron configuration so we

Got 1s2 okay so we’re going to slide down again here this would give me 2s2 pretty easy so far huh 2p6 and then 3s2 so far so good this is amazing all right then we come back to the top of the slide we get 3p6 and then we go to 4s2 now we’re going to stop there because if you look at this 2 and 2 6 and 2 and 6 and 2 make 20. all right that’s pretty cool now

Let’s look at our orbital notation verbal notation deals with hund’s rule hund’s rule states that for every sub level you have to put an up error first before you put the down arrow so let’s look at 1s it only has one sub level so we go up arrow and then down there same thing with 2s just one sub one up arrow down there but with 2p we got 2px2py2pz so you’re

Going to go up arrow up arrow up arrow then we’re gonna go down arrow down arrow down arrow pretty darn starting up three s one sub shell pretty cool huh so 3px 3py 3pz would be up arrow up arrow up arrow and then down arrow down down there the forest too would be up arrow and then down now let’s look at a noble gas notation what’s the nearest gas to calcium

That’s noble well of course it’s going to be argon right so we’re going to use argon as our noble gas put ar in there and let’s look at our valence shell the last possible shell that can hit electrons that would be argon four s two that’s pretty easy huh okay what about a quantum mechanics well what is the n value and that says what period does calcium resin

Well calcium is in period four so the principal quantum number would be four but notice that calcium is in the s block right so the angular momentum number would be zero same thing with our magnetic number it’s in the s bar so the value is also zero i’m gonna put a zero right there now look at the last arrow it’s going down so that means our value is going to

Be one half negative well that’s it you guys be snarly we’ll see you back here at lucine chemistry

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Electron Configuration of Calcium Ca Lesson By Moosing Chemistry