 So, next we write down unequal contributing, unequal contributing resonating structure. Write down in this case, we cannot find out the exact value of bond order, the exact value of bond order, but we can find out the range of the bond order, exact value they would ask you also in the exam for unequal contributing. So, in this one example you see range of bond order, we can say bond order lies in this range, like the first example I have already taken this example C H 2 negative C double bond O, now the resonating structure of this is what? C H 2 double bond O minus an H, these are equal contributing yes or no? How do we find out equal contributing or not? No, no, how do we find out equal contributing structure? If the stability is same, correct? Are they have they have same stability? No, no, because for this we use the rules of relative stability of resonating structure. Obviously, this one is what? This one is less stable, because negative charge of oxygen, so now when you have the rules, you will have the idea that what rules you have to apply, it is not a social rule, rule 1, rule 2, then directly you can apply, directly you see equal pi bond, oxygen on negative charge, carbon negative, this is more stable. Now when this is more stable, so this contributes more into the structure, correct? Now if you have to find out the bond order, bond order of carbon-carbon bond for this quality, okay? Exact value we cannot find out, but we can say the bond order of carbon-carbon bond lies in this range, first of all this 1 to 2, because here we have 1, here we have 2, right? Now since this one is more stable, so this contributes more, right? So we can further write that the bond order lies in this, 1.5 and 2, right? Understood this? So we can write down the range, we cannot write down the exact value in case of unequal contributing structure, okay? Now what is the bond order of carbon-oxygen bond? What is the range for this? It is 1 to 1.5, clear? So for this you should know the rules which RS is more stable, accordingly you can write down the range of bond order, got it? I will write down some examples, okay one example write down. Sir if the contribution like 60 percent, 40 percent then the bond order we can read. That is difficult to judge, 60, 40 or 70, 30. That is why we will write down range, we cannot write it like that, okay? Next one you see, chlorobangene, have you heard about chlorobangene? Yes. What is chlorobangene? Suppose it is bond A and bond B, carbon-chlorine bond, right carbon-chlorine bond. Tell me the bond order of A and B, bond order comparison of A and B. This one is chlorobangene, this one is what? Cyclohexane, chloro-cyclohexane. The first one is, yes, first one does not have that word, it is cyclohexane and chlorine bond. B is more stable, why? Here we have resonance, do we have resonance here? Do we have resonance here? No. Here we have resonance, this is pi-sigma lone pair conjugate system. So we can draw the resonating structure, right? So when you draw the resonating structure, we will have partial double bond characteristics here. That is why, it is negative double bonds and double bonds C L, positive. So partial double bond characteristics we have between carbon and chlorine, that is why the second bond order is more, bond order of B is more. Can you say what is the aromatic? No, no, we are talking about this bond, aromatic is this ring, we are talking about carbon-chlorine bond. Can we say that the whole thing has more valence to it, so that is more stable. See, no, no, no, this is a bond resonance of each other. See, point is, this is the different molecule, this is a different molecule. Over the stability if you ask me, this is aromatic compound, because ring is more stable, obviously this one is more stable, but here we are trying to find out the bond order of carbon-chlorine bond, like I said, bond order of two atom will say in a molecule. So we are talking about bond order of this bond and this bond, since here we do not have resonance, bond order of this bond we can write. Bond order is one, exactly one, but here it will be between one and two, right. Obviously the bond order of B, bond order of B is more than that of, that is why aryl halide, chlorine on benzene, right, that we call it as aryl halide, when you remove one hydrogen from chlorine, it becomes aryl. Aryl halide is stronger than the normal alkyl halide, because of resonance, because of this resonance it develops a partial double bond characteristics and it is difficult to break, okay. So in comparison alkyl halide and aryl halide, aryl halide is more stable, carbon hydrogen bond is more stable than carbon hydrogen bond is alkyl halide. Exactly, it is stable. First one, first one. First one, carbon-chlorine bond is more stronger. If the second one is less stable, so won't it want to change back into the first structure? That is a different thing, but it has some partial double bond characteristics, because of resonance, because if this delocalized will be there, continuously there, if you draw the actual structure, the actual structure is this, partial double bond characteristics. That's why the second one bond strength. And we know the order of bond length and bond strength. Bond, order and bond strength is? Directly. Directly. And bond length is? Inverse. So any one of these questions, if they ask in the exam, you can compare it. Okay. This question, tell me, bond order of alpha, beta, bond. Yeah. This is alpha. This is beta. And this is? Oh, it's a whole. Alpha means this carbon-carbon bond. Okay. Beta is this gamma. So that's the bond stability. Bond order. Bond order of beta is? The alpha. The highest beta and alpha is gamma. It is. Oh, it's alpha, beta, gamma, not normal. Beta, alpha, gamma. Beta, alpha, gamma. They are not normal clature. No, no, no. This carbon-carbon bond is alpha. Carbon-carbon bond is beta. Carbon-carbon bond is gamma. Like here, we have carbon-carbon bond is A, carbon-carbon bond is B. Which one is the most? Beta. Beta. What is the bond order of this? It's two. And what about this alpha? One, two and something. One, two, two. Right? And this one is? One. Right? So beta is max. Then alpha. And then gamma. Okay. What about this one? CS3. CS2 double bond, CH. OH. OH. And CS3, CH2, OH. Carbon-oxygen. Alpha, carbon-oxygen. Beta. Alpha, beta, comparison. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha. Alpha is more white because it shows us. Here we have resonance possible. No, it shows the two states. It is not paired. They won't draw in the exam. You have to know this. When oxygen bond is in two bonds, it has two lone pairs. It is conjugated, right? Yes. This is conjugated. This there goes partial double bond characteristics. And that's why the bond order of alpha is more than the kind of beta. Okay. Bond order of alpha and beta. Why? Sir, this has more resonating structures than this. So? Sir, if we do the dimensions by number of resonating structures, this one will have less. Alpha is less. See, we have this lone pair and this lone pair. And because of this resonance, it develops partial level bond characteristics. Right? So here the bond order of beta is what? Less than two, but greater than one. Okay? Alpha bond order is what? It is one here. In this molecule, there is no resonance. No resonance when I say it means this lone pair is not involving resonance. Why? Because there is conjugation, but because of this group CS3, there is a static repulsion here. And because of this static repulsion, this group changes its plane. So the entire molecule is not plane at all. Okay? So this CS3, one of the CS3 will go into the plane. You know this bond? It is coming out of the plane at arc range. And this wedge is into the plane. So what is the plane? There is something. How is it not closed? How is it not closed? CS3. This is CS3. This is CS3. See because of this two group present, we have a static repulsion here. Right? Static repulsion means hindrance. Both this CS3 and this CS3 are pushing each other. So because of this hindrance, stability decreases. Right? And to minimize this hindrance, what happens? The plane of this molecule will change. It rotates to minimize the repulsion and adjusts the... Static repulsion is the repulsion here. This group and CS3 repulsion. See, but why doesn't that CS3 and that carbon... That's CS2. Not that much to repulsion. If you have this group present, O-C double bonds is bulky group. Right? And if any group is present, here suppose cyclopropyl like this, then since these two groups are big, so we have a static repulsion. Right? Both groups will push each other. Right? And because of this static repulsion, that stability decreases, you see. So here also we'll have this static repulsion. Right? See, this question, if you get in the exam directly, you'll do it wrong. If you don't do it, you won't know. That's it. Organic chemistry is like that only. You'll see many things where the... No. The basic logic won't apply. You cannot say. You can ask where we consider this static repulsion. Right? You can ask this question. So I can say when there's bulky group attached. Right? So because of this static repulsion, stability changes and you should know when you have to apply. Or the polyethylene group present, and this thing is present, this will have the static repulsion. And to minimize this repulsion, it changes its plane. And you don't have to do anything into it. It adjusts in such a way so that the repulsion is minimized. Right? So what have it conjugated? Because... Up this repulsion, the plane of this and this will change. So it's one, it's like this, another one is like this. So it's not parallel orbit. No resonance. No conjugation, no distance. Sir, is static repulsion the same as static hindrance? Yes, correct. Static clouding, static repulsion, static hindrance, all are same things. Okay? Static clouding, static repulsion, static hindrance, all are same things. So because of this static hindrance, this NH3 hole twice changes its planes and this becomes non-plane and now the entire molecule. And hence the resonance is not possible. Write on this example properly. Okay? So alpha is one, beta is this, so the bond order of beta is more than that of... Sir, there was only one bond there and the right one was very stiff as a bunch. Which one? The bond of the bonds. This entire thing will be under repulsion. Only this bond is there. Only this bond is there. That is what the difference between the two bonds. Done.