Quantum Numbers Explained 🔥 | All 4 Quantum Numbers in Easy Language | Class 11 Chemistry

So, kids, today I'm going to tell you about quantum numbers. I mean, you'll be able to analyze this here today Where are electrons actually present? We have been told according to this quantum number Where exactly are electrons present in our orbitals? Before teaching this, I would like to briefly explain a few things to you. Let me tell you, the child, just like you, needs to find me out. So where will you look for me first? First of all, if the world's If the map remains, will you prefer me in India? Like I'm in India, okay, after India, Maharashtra Presenting one that is your azimuthal quantum Number three is your magnetic quantum number and The last one who came at the very end is fine, after quite some time Here comes the fourth spin quantum number, which is Basically, let me tell you one thing—what are these people? You know where your electron is located The probability in this orbital is correct, right? Electrons inside atoms or in orbitals Where are these present to us, the principal quantum? Which shell in our atoms has electrons of this type? I'll tell you about the principal quantum number. Come on, hurry up and come here right away, first of all, inside the principal quantum number We read that we identify the shell of the electron. I mean, we are identifying here which shell the electron is present in. You must know, you've been reading certain shells The quantum number here indicates that I am good to you. I represent the first principal quantum number as n. Represents this shell tells end second The child who has the value of the principal quantum number, right? They always come in positive integers. Positive Integers mean that the value of n you have will be understood in this context, this too. It will be three, and so on, telling you the value of n as if he's always taking positive integers, look If I have the value of the principal quantum number here One I take, two I take, three I take, four I keep, so what does this represent? They represent the sales here, just as you have First shell is called K shell, and the second one is also correct. So, after K, what comes next? Look: KLMN. Now listen carefully, children. This K shell here, then the one that follows The L shell is present; how many orbitals are there on it? So, the formula to find this out is What happens, happens. allowed orbital here I am writing to find the allowed orbitals The formula that is used That's n raised to the power of n, meaning What is it, that if you When talking about the K shell, the value of n is 1. 1, because the number of shells there is 1 Alright, so if I put 1 here So here is the number of allowed orbitals How much will it be when 1 becomes k? The charge will be deducted, okay, What does this mean, that inside the K-Shell here, How many orbitals are there? Later, we will study orbitals. s, p, d, f are our orbitals. Inside the K-shell, there is only one orbital allowed. Inside the L-shell, there are 4 orbitals allowed. and inside the N shell, the one that is even larger I mean, the M shell is larger for you. Inside it, a total of 9 orbitals are allowed. and KLMN N shell, the larger your own becomes Alright, due to which there are 16 orbitals allowed here So, what's the shell size? Look from top to bottom. So it is increasing. What's happening? It's increasing, okay, so here Actually, it's about the KLMN shell. Where are the electrons present? Where is K? Where is L? Where is M? It is said that about the shell, it is said Yes, and here you have noticed another thing: the child's K-shell How many orbitals are there inside the L-shell? four exist, and there are nine orbitals inside the M-shell now these orbitals Later on, you will understand exactly what orbitals are. Alright, let's move forward, kid, Our second quantum number is the azimuthal quantum number. Alright, I'm currently in India, okay? Now I will come into the shell, leave the shell, and enter into the shell again. and that is called orbitals, okay, that I And here, the value of L So It goes from 0 to 2^n - 1. I'm telling you this. What is 0 to n-1? n is nothing but your principal quantum number So here's what I heard, pay attention A formula comes here that L is equal to n-1 L is equal to n minus 1 As I find out That my child is inside the K shell How many orbitals are there inside the K shell? So, what was the value of K? It was 1. Alright, just put it here. L is 0 + 2, what will it become? What will be the value of L when N-1 is 0? Alright, after K, whom shall I pick? After the child K, I will take out L. What was the value of L? 2 So, what was the value of L? 2 So what is the formula here, my N? What do you mean, KLMN? What's yours? KLMN is stating the same number of shells. Well, that is the value of N on one side. So here it's 2 So if I do 2-1, how much will it become? 1 So you can find such ones for klm, 3 and n What is the value of n? 4 So, in short, you'll get the result here, like 2 here. It will come, and here you will get how much? 3 will come. Alright, so listen carefully now what 0 1 2 3 are specifying Yes, this symbol represents this symbol here. But we will give the symbol. A symbol Representing That's your one task: available child who has 0 1 2 3 for you, right? This represents your symbol. What is that symbol which at times is yours? It's the duo and the Beatles, and three I, so that's it. The point is, basically, the numerical value of your If 0 1 2 3 comes, then s for 0, p for 1, and d What will be the value for 2 and for f? 3 So, you'll have both 0 and 1, so you might also have s, and p will definitely be there. Okay, so sp will be, m will be, so spdf will be; check here, the number What's happening here with the orbitals, are they increasing? The number of orbitals is increasing here, so it means you are here Do you reach the orbitals in the azimuthal quantum number? The electron is in our s orbital, p orbital, or d orbital I'm fine, you've already found out all these things, that's fine, right? I have arrived in Maharashtra; I am now in my Maharashtra. I've figured it out, that's fine, so the azimuthal quantum The number represented by l is yours We also refer to this as the subsidiary quantum number, and here basically You will find out which orbitals the electrons are in. I have spdf. If you solve the value of anyone, it's fine, for example, if you know It's gone, that your electron in the K shell, whose value is 1, so you have this If the calculation of the azimuthal quantum number results in 0, then you will know Subscribe Now, which quantum number is the magnetic quantum number? number now comes the magnetic quantum number, denoted by ML They represent the magnetic quantum number, not the others. provides information about the spatial orientation of orbitals in the given subshells Okay right now what you have Show the suborbital, then show the subshell, but first you showed the shell. K L M N You have just shown the subshells s, p, d, f, correct? What will be the spatial orientation of that subshell now? It indicates what the orientation will be, the magnetic quantum number. Now how will you figure out the orientation of this guy, okay? I'll tell you, listen carefully, a numerical value comes in, He can figure out what its orientation will be. Listen carefully, first of all, there is a formula for the magnetic quantum number, ML equals 2L, this is L, 2L plus Suppose the child finds out that you are here, let's say It has now been determined that the value of your L is 0, correct? What is the value of L? It is 0, okay. Now, if L is 0 Now that we've found the value, let's plug it into this formula. ML is equal to what? So 2L plus 1 and You know, zero means the s orbital, right? The number of orientations for an S orbital will be one. He will be the only one, there will be one orientation, the other one will be removed. Suppose you find out that the value of L is 2 in my case. How much is this? It's 1. Sorry, it's 1. Alright, so it's 1, so let's apply the ML formula. ML is equal to 2L plus 1 Alright, you'll understand this right away. 2 into 1 plus 1 Okay So this will become 2 plus 1, how much will it become? 3 So, you're not getting 3 orientations for P, right? How many orientations are coming, 3, one more and I'll do it, That was for the P orbital; for the L value, you get 3. For 3, there is a D orbital, so you can also figure that out here. ML equals what? ML equals what? 2L plus 1 Alright, let's see, 2 times 3 plus 1, so what will it become, 3, 2, 6, 6, 7, Reading, there are 7 numbers there How can you show this formula Given this, you can show me as I tell you How to check the value of L? It is 3. So if you put it here, it will become 3. Minus 3, okay, I'll tell you such a thing. Look, I'm showing you an orientation. You'll write just one orientation, that's fine. But if you need to show three orientations, the child So, listen carefully to the three orientations—how you can appear Then go from the lowest to the highest of you all. If you look in the lowest, the first number is 0. Alright, then what happens on the zero side? Plus 1 and here what happens is minus 1 So you can see here, I've got 3 orientations Show me ML now you have Show me the 7 orientations, show me the 7 orientations How do I turn it on from 0 now 0, idhar plus 1, idhar minus 1, idhar plus 2, idhar minus 2, okay, So, how many are there in total here, 1, 2, 3, 4, 5, and this makes 6, And it became 7, so how many total orientations are there now, kid? Seven orientations have been completed, okay, so this is the mathematical relation. You also form 7 orientation of orbitals later. dk, double, double, shape, okay, that too, I It turns out that if the lowest zero is present, then you should inform me at that time. So you know the mathematical term that plus 1 can be taken Here, if we can take minus 1, then these 7 numbers It's fine for you to write like this; you can also write from here. As I have written 0 here, after that if you take l If you put the value 3, then do 3-2, how much will it be? It will become 1, it will come out. Then, if you put 3 minus 1, it will become 2. It will go, okay, so according to this calculation, you can also input these values here If you can write, there's just one way to write an orientation, okay? So, this is your magnetic quantum number, which indicates that How many orientations do your SPDF have, and how many different ones are there? It has orientation, right? Just like S has only one orientation. is because you will later realize that S is spherical for you But then three orientations inside Andy's seven orientations Okay, right. Oh, what was it again, sir? Roof S1? P2P this too For S P G 2 Let's go with the question I have Here are three You took it, right? Come on, kid, what's up with three? Isn't it your d orbital? Right, I mean, isn't it that three of yours? Your f orbital, check it here, look at this, the three If the value of l were three, you would have an f orbital, and the child who There is an f orbital; here, just write 'f'. Orientation is seven; you also do it for D. You can, okay. K is for L with respect to D. How much should I keep? Two, okay. Sorry, there was a mistake here. Okay. So for d, what value of l needs to be set for d? Two, okay, so this is one. Alright, okay, so this kind of orientation, you know Magnetic quantum numbers indicate, right, this is yours It's an f orbital, not a d orbital. What are the seven orientations in an f orbital? Let's do it for d as well. Let's move on to the next one. The electron spin quantum number, which is the fourth one, is yours How do electrons reside in an orbital? Look at one thing first — electron spin Quantum numbers represent this, children, these are specific. specifies the spin of the electrons in the orbital Inside the electron orbital It tells how to spin. Yes, okay, around the axis means that electron itself What do you keep doing on your access? Keep rotating endlessly. I'm showing you the diagram, look, the electron's access What do they keep doing? They keep rotating. Okay, so it does Imparts angular momentum, due to which they acquire what? Angular momentum has two types of orientation. There are electrons here, and one of them has a half. The second one is plus half and minus half I'm telling you Let me tell you what plus half and minus half mean, for example If I take any one orbital, I take any one orbital So, child, the way to represent an electron is either Does it point half up or half down? Because in one orbital you can fill a maximum of 2 electrons The one pointing upward is plus half. The one pointing down is minus half. Because one will have an upward arrow, the other will have a downward arrow, okay That's how it works—spin up and spin down. Half plus half minus, okay So an electron can have a maximum of Two electrons can fill it. plus half minus half Okay So, in this way, what do electrons do in our orbitals? present are those located at opposite points It is written, but one will remain on top. One will stay below, okay? So, the child, this entire thing was your quantum number. where you find out that the electron is yours How do they stay present in orbit? Where you saw SPDF How many orientations do SPDF have? Like S, it has only one orientation. But in P, there are 3-3 orientations. There is 5 in D, which I haven't mentioned yet. You figure it out yourself, and in F, the child has 7 orientations. There are seven types of lobs in it: the dumbbell lob, okay, We'll see all that ahead, come on, I think all the children The concept of quantum numbers will become very clear in a very excellent way.