Energy levels, sublevels, & orbitals

public video about energy levels sub levels and orbitals all parts of the atom and about how electrons are involved in these parts and where we can locate them so the whole point of this video is this chapter focuses on electrons where are the electrons in an atom that's what we're going to get at in this video and start so let's first refresh our memory and take a look at hydrogen so if you remember hydrogen has an atomic number of 1 and let's just remember from first semester that the atomic number is the number of protons and if the atom is neutral then we know our protons are equal to our electrons that's what a neutral atom is there's no leftover charge so if hydrogen has one proton then it has one electron we'll assume it's neutral so it's this one electron that's what we want to focus on where in the atom is this one electron and that's what the point of the video is so I have drawn a hydrogen atom for you and hydrogen has one energy level we'll learn later on in this video how to figure out how many energy levels we can also call this energy level a shell so this is the first energy level is the closest to the nucleus also called ground state the first energy level and only the first is the exception it can hold up to two electrons meaning it can hold less than that but no more than two every other energy level from there on out can hold up to eight so if my hydrogen only has one electron then let's go ahead and fill this in here's the one electron okay I'm going to use little dots represent electrons so for the sake of argument we're going to put an electron either here here here here we'll kind of see there's a little bit of a pattern that I use so I'll put the first one up there alright okay let's take a look at another atom how about carbon well carbon has an atomic number of six on the periodic table again we know that's the number of protons and if carbon is neutral those protons equal the electrons and so we'll assume it's neutral therefore six protons means six electrons again our focus are the electrons how do we fill the electrons in an atom so like we learned last example the first energy level or energy shell or just we can even call it a shell can only hold up to two electrons so one two what's happened bottom can it hold anymore no well we said that there are six electrons we just got rid of two of them so there's four more left the second energy level in all the energy levels from there on out can hold up to H no more than eight it can hold less but no more than eight again we add six and we used up two which mean there are four electrons left so let's fill those in one two notice my pattern three four again total of one two three four five six so again first energy level holding to the second energy can hold up to eight but it's holding six okay that's great let's look at another example sodium sodium has an atomic number of 11 so we know it has 11 protons and 11 electrons if it's neutral and we'll assume it is sodium has one two three energy levels again you'll learn about the energy levels in a second so I have 11 protons remember the rule the first energy level can only hold up to two so there's one two the second one can hold up to eight so one two three four five six seven eight okay all right so that makes ten right eight and two makes ten I have one more electron these are my total electrons so I need to use an extra energy level to get that - now 11 electrons so if you care about the black that's a total of 11 electrons just a reminder where are my valence electrons remember the outermost energy level is where I found my valence electrons and there's only one valence electron here on sodium okay how about hydrogen valence electrons one valence electron in hydrogen that's why they're in the same column how about carbon whew outermost energy level one two three four that's why carbon is in column four on the periodic table just a refresher okay so now that we've seen how these electrons are filling in let's go back to some of our terminology and refresh your memory an energy level as we just saw has a sublevel within it and within the sublevel there's an orbital and again I like to use this analogy hopefully this is looking familiar then an energy level represents the floors in a hotel the sublevel is a represents of rooms and the orbitals represent the beds in the room and remember this is how we actually can find or where we can find electrons so electrons are actually kind of like sleeping in the beds that are found in the room that are on the floor of a hotel so kind of like where can we find you you are in a bed that is found in a room in the hotel floor so let's take this analogy just one step further and look at this okay so this represents a piece of the pie and if we think of an ad on being a circle and then I've just kind of cut out a piece of the circle okay and if you notice here I have energy level 1 and is equal to energy level energy level 2 3 and 4 1 is the smallest ring and so it's very very very small there's not a lot of room the only sublevel that there is an energy level 1 is sublevel s in energy level 2 there's sublevel S and sublevel P in energy level 3 there's sublevel s P and D and in energy level 4 there's sublevel s P D and F so now you know the names of our sub levels they're actually just letters okay all right now in sublevel S there's only one orbital sublevel S one orbital sublevel S one orbital sublevel S one orbital in sublevel P there are three orbitals wow that's a lot three orbitals and P three orbitals and P in sublevel D there's five orbitals five and sub low F which you notice doesn't happen often there are seven orbitals now to help remind you about this or help give you an analogy here's the hotel that's back you go to the first floor which is our energy level and you go to the room s which is a sublevel and you open that door and there's one bed two electrons can fit in one orbital one bed now I go on to the second floor the second floor is even bigger and there's more room so I have named s and room P as always is there's going to be one bed so two electrons can fill in there and in room P there's always going to be three beds so I've got two four six total electrons can fit in there okay and I go to the third floor there's even more room on the third floor there's room for room s room P and room D remember room s always has one orbital POS has three and now we see D always has five look how many more electrons can fit it remember each bed or or bad doll can hold up to two electrons now let's look up here on the fourth level I have s P D and F we said s holds one bed P holds three and D holds five and now F holds seven so two electrons can fit here 6 right 2 4 6 8 10 and 14 electrons can be held in the F and it keeps going on but for our analogy right now this is good enough ok alright so with that being said there's actually a way you can arrange the periodic table or the periodic tables already arranged that can help you out with our sub levels this is really good to sketch down this section the periodic table the first two columns are the S sub levels the middle transitional metals happen to be the D and the elements to the right which are mostly nonmetals but some of the metals are the P we call these the SDP block down below the Anthony's left acting isin lanthanides are the

Channel: Sonya Birazian

Views: 398,145

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Id: kXfaQEkWXFM

Length: 9min 35sec (575 seconds)

Published: Mon Feb 24 2014