 What types of odd electron bond we have, 1 electron and 3 electrons bond, we call it as odd electron bond, we also call it as half bond. Since its bond order is half its bond strength of an odd electron bond strength is less than the bond strength of single bond. In which odd electron bond is present, we call it as paramagnetic bond. Examples of this, like I said only two examples we have to remember. N4, N4 2, N4 and N2. N2 has the bond order is this has 3 electron bond. In this we have 1 electron bond present, 1 and 1 electron bond. Because you see, this one you see, how many electrons? 50, right? 50 electrons. When you draw the configuration of this, there is a sigma 1s, sigma star 1s, sigma 2s, sigma star 2s, sigma 2p z, sigma 2p y, 5 star 2p x, 5 star 2p y and sigma star, right? When you distribute the electron here, 2, 4, 6, 8, 9, 9, 10, 11, 12, 13, 14 and 1 here, 15. What is the bond order you get here? 2.5 4, 6, it is same. Same value, 5 divided by 2, 2.5. Bond order is 2.5. That's half, 0.5 that you have, that means it has an odd electron bond. Okay, so this... Draw the loose structure of N0. Loose structure of N0? No, it's not, because it's not an electron bond you won't get here. And that's why it is different. Why I am drawing this you will understand. This has 11 valence electron, right? So 1, 2, right? 3, 4, 5, 6, 7, 8, 8 plus 2, 10 and 1 electron. It's not similar to the molecule that we did already where we have even number of electrons present. So when you place this balloon pair of electron here as a bond pair, this what happens? This bond pair, this non-pair converts into bond pair here with the bond electron or electron of nitrogen also. So this is not normal of the usual loose order structure that we have in other molecules. That's why we generally don't draw the loose order structure of the molecule which contains odd number of electrons. But you have to draw the molecule will be this. So it has 1 double bond and double bond O with one lone pair and one bond also present which is an all electron bond contains 3 electrons. The bond order of that third 3 electron bond is half, 2 bond we already have. That's why it is 2. So which electron is larger? Where? 6 plus 5. So we have 11 electron. Yes, so that's only now. So there's one lone pair on hydrogen. So we'll have one lone pair. So it's not a normal bond. You see, first of all, why we are drawing the structure here because bond order says that it has 2.5 bond order. Means 2 regular bond we have, one half bond we have, odd electron bond. That's why we are not moving only one lone pair near to make a triple bond. It's not 3.5. That 3 electron bond is 0.5. Sir, what is 1? 0.5. 0.5 is also 0.5. Sir, if you go to that, it has an octave to go. What? See, according to this we are drawing the structure. Bond order of NO is what? 2.5. So when you draw a triple bond there, it's bond ratio to 3 which is not we are getting. That nothing is absolute here. Because of no, because the bond order is 2.5 for NO. That's why the noise order is what it is. And we suggest that we have an odd electron bond. If you write a triple bond there, simply draw a triple bond, then its bond order should be what? 3. Which is not we are getting. So according to that bond order, what should be the structure? It has one odd electron bond or a half bond. That's why the bond order of odd electron bond is always half. And we are getting 2.5 there. Sir, we have not finished the order. No, no, no. See, they have their tendency. But when you draw the structure, it should define the bond order of that bond. We have to draw that structure according to that the bond order must be defined. That's why we are drawing an odd electron bond. All the molecules where you are getting 0.5 as the, you know, bond order. That 0.5 means what? We will have an half bond. Odd electron bond. Odd electron bond is 1 electron and 3 electron bond. Very rare. Like I've given you NON, NO2. In NO2 we have 1 electron bond present and here we have 3 electron bonds present. Only that 2 you need to remember these. So we are drawing this structure according to the bond order that we are getting. How much are you going to get? Find out how much are you going to get. My point is we will have an odd electron bond order. 3 electron. Sir, what is the odd electron bond? One electron bond or 3 electron bond is an odd electron bond. It has half bond character. That is the experiment that you need to remember. That's why I have written it over there. NO3 electron bond, NO2 is an odd electron bond. You won't get more than these. Only you need to understand that wherever you are getting 0.5 it means there is a half bond present. That's why 0.5 is a bond order. Point bond, the bond order is 1. So 0.5 means there is a half bond present. That is an odd electron bond. Okay. See NO is, no, NO is, it means the ligand. And it may show positive charge on it. It may show, it may have neutral molecule. Ligand is electron by donor. It's donor is electron by donor. Okay. So Nitro and NO in some of the forms they have invented, they have as positive ligand. It's a bit, we call it as Naughty Ligand. Okay. They pay neutral as they pay positive ligand. Okay. That is also, then the test then give us the little round ring test. Okay. Round ring test. Okay. So, this we need to know. You need to memorize this. I don't think it will be positive charge. It will be difficult because there is a odd electron. There is some kind of value you must be getting. That's why I am not calculating formal charge. But if you want to know what charge present on the nitrogen, that idea whether it is positive or negative value, let it be. That you will get the idea from formal charge. What is the charge between the between the two? Yes, you can see. Overall it should be neutral. So, one is positive other one is negative. Equal value. NO is nitrosil. It is nitrosil. Okay. And NO plus is nitro CEM. So, as far as I know we have this in coordination chemistry. Okay. But you need to know what is the significance. See, when I say boron is 0.5. So, what is significance of this? It means it has an odd plus mean. Right. NO has 3 electron bond and NO 2 has no influence. So, next chapter we are going to start. It is the states of matter. What are the states of matter we have? What have you done? We have done this chapter in the school. Right. What is the states of matter? Solid, liquid and gas. Any other? Plasma. Plasma. That is very heightened. Very heightened. Right. So, in general there are three different states of matter we have. And that is solid, liquid. What is the difference between among these three states of matter? What is the major difference in there? Why we have a major difference in there? Intermolecular. Intermolecular force distance interpretation. Major difference is what? Intermolecular. There we have maximum intermolecular force. Solid. Right. IMF, for solid is maximum and then for liquid and for gas it is, gaseous molecules have minimum intermolecular force of attraction that's why in any case if you see the motion of gaseous molecules they have random motion right, it travels in all directions randomly because they have minimum intermolecular force of attraction right, so two gaseous molecules the interaction between the two is very less over here, minimum and hence they have random motion okay, solid molecules are strongest because they have strong intermolecular force of attraction that's why whenever you want to take some solid species you have to apply some force of attraction right, liquid molecules have in between the force of attraction that's why it can flow right, so when you increase the intermolecular force of attraction the molecular motion is right, it will be less, solid molecules will not move as compared to the liquid and gas okay, here in this chapter we are going to discuss about the gaseous state okay, we have solid state also that is in dual standard I don't know whether they have changed the slivers or not because last year I dot the solid state in 11th standard in Raji Nagar okay, but somewhere they have taken this in 12th standard okay, so whatever it is but solid state and liquid is a gaseous state we will discuss in chemistry, liquid state will not move as compared to fluid mechanics right, so all these three states we have to study in 11th and 12th standard, solid and gas will study in chemistry, liquid will leave and study in opinion right, so gaseous state you see the major difference is what major difference is the intermolecular force of attraction right, so if you increase the intermolecular force of attraction by any means right, so we will have a range of intermolecular force in which the molecules lies in this solid state, for a given value of IMF we will have liquid state So, when you increase the intermolecular force of attraction, gas has tendency to convert into liquid and then into solid, okay. So, since the intermolecular force is high or maximum here, so whenever you have, you increase the intermolecular force by any means, okay, intermolecular force between the two molecules increases, then they have tendency to change their state, right. For one value, gas converts into liquid, further you increase, liquid converts into solid, when you put water into the freeze, then what happens then, converts into ice, why it happens, why ice converts, sorry water converts into ice, particles reduce and how they reduce is because in the freeze we have low temperature, right, temperature is very low, see the molecules are what, molecules are randomly moving, right, these molecules of any state, they have random motion, right, so by any means, if you increase the intermolecular force of attraction and how do we increase that, when the interaction between the molecules increases, correct, if the molecules are moving very fast, right, their interaction will be less, right, it is difficult to, you know, see who will be inside and what will be, but because the speed is very fast, you cannot interact, right, so when the two molecules, when the two molecules pass at each other with very high speed, they have very less tendency to interact with you, right, and if you decrease this velocity, right, interaction increases and then we have possibility that this converts into liquid and then into gas, right, so point is we have to increase the intermolecular force of attraction and that we can increase by decreasing temperature, low temperature means low kinetic energy, low kinetic means, low kinetic energy means what, less velocity means more interaction, okay, so one possibility is to decrease the temperature, that is why in lower, in freezer we have no temperature, so water molecules starts interacting with each other and then it converts it to ice, so another one is what, high pressure, if you increase the pressure, the gas molecules comes closer to each other, right, and when they come, when they come closer, then what happens interaction will be more, right, two factors we have, one is pressure, when we increase the pressure, another one is when we decrease the temperature, now states of matter make it change into these two conditions, correct, how this conversion takes place that we will also discuss in liquidification of gas, that is not ideal gas, that is the equation of state, if number of moles and volume is constant, so what I am telling you that first of all it is not gas, I am talking about the, you know the change in state, I am talking about the change in state, when it is possible, either you increase the pressure or you decrease the temperature, when a state change is there you cannot apply previous goes to another, but that is gaseous law that is only applicable to gaseous law, okay, I am talking about something else, suppose if this gas has to convert into liquid, what you will do, you will increase the pressure or you will decrease the temperature, because eventually we have to increase the intermolecular force, intermolecular interaction we have to increase, that is what we are discussing, anyways, so all these things we are doing, look at a time, at a time if you are increasing pressure fine or decreasing temperature also fine, but both if you are changing then both should be, either you should, both you cannot change, or you can change also, that is very easier to convert the phase into that, but again like you cannot compare this with previous goes to another, because that is only for gaseous, okay, you can change both or any one of the two.