 Next you write down then all of you guys Let me know if you are done. I'll just go to the honor slide another page Okay So now like I said in case of association or dissociation the Collegative property changes because eventually what is happening in both the cases the number of particles in the solution The number of particles in the solution Increases or decreases changes basically Okay, so now you see in case of association. How we will calculate the value of went off factor I? Okay, so first one you write down First we'll see what is the formula of I? Okay, and then we'll Discuss this association and dissociation. You see went off factor went off factor Which is I? Represented by I this you can actually compare with With the Compressibility factor in states of matter Okay, more value of Z more will be the deviation from ideal gas behavior. Okay, that's what we did Compressibility factor Z. Similarly here. We have I more value of I more will be the deviation from The colligative property the expected colligative property Okay, so this is one thing, okay Now you see the formula of I we have the went off factor I it is given as I Is equals to went off factor because this formula base question also they ask sometimes so the deviation from So I is equals to the actual number of particles Right on this actual number of number of particles after dissociation or association or Association this divided by this divided by The number of particles Initially dissolve the number of particles initially dissolve, right? We can also say because it is the Expected actual number of particles after dissociation and association this also we also Call it as the normal colligative property divided by abnormal Okay, so like you see the another term also will write down which is I Is equals to the actual right actual or We also write it as observed actual or observed Collegative property CP is the colligative property divided by divided by The theoretical colligative property theoretical Collegative property actual by theoretical Okay, in terms of more molar mass also we write it as Okay, in terms of molar mass what we write the normal molecular mass normal molecular mass of solute divided by abnormal molecular mass mass of solute Okay, so this is the formula of I correct, how do we calculate this in terms of dissociation or association that will see Okay, so first condition you write down when association takes place in case of association in case of association Okay, so write down in this in this the number of solute particle in This in this the number of solute particles is less than the expected value association the number of solute particles Decreases Okay, so number of solute particles is less than the expected value Okay, like for example, you see benzoic acid Example of association was in the benzoic acid will have dimerization tendency Okay, so benzoic acid have the tendency to get dimerized and hence the number of particles decreases Correct similarly in this you see like association How do we find out I? Here right, you see one general example. I'll write down here Suppose we have this I'll go to the next page, right? See suppose I am assuming a like a Oh No, the polymerization process here and number of molecules a and this clubs together Forms a and this is the association case So what happens here suppose at t is equals to zero? At t is equals to zero we have this has a concentration and this is zero So when it forms this so this will dissociate and gives a minus a alpha And then we get here a alpha by n How many of you understood this tell me first all of you understood this? A minus a alpha n gives one so one gives one by n a alpha gives a alpha by n right this you see here this is the This plus this is the total number of particles initially right at t is equals to zero and This plus this is the number of particles at time t when the association takes place So the number of particles after dissociation divided a total number of particles initially present so with that Formula I is equals to what we can write the total number of particles after dissociation which is a minus a alpha Plus a alpha divided by n and This whole divided by the initial number of particles which is a okay So when you solve this I is equals to you will get I Is equals to you see this a gets cancelled here this this this and this and we'll get I is equals to one plus One by n minus one into Alpha this is what we get formula is this one plus One by n minus one into alpha okay So now when you also write down in this way I is equals to I is equals to one minus One by one minus One by n into alpha this also we can write minus I'll take common outside Right n is obviously it is more than one right and this n is what n is obviously it is more than one So one by n is less than one right means this term is positive Right. This means what the value of I in case of association is less than one. This is one important Condition we have the value of end of factor in case of association is less than one so In those formula you can write the number of actually the the actual calligative property Divided by the theoretical calligative property is less than one so with this Data what we can write the actual calligative property because this question you will get in the book actual calligative property is Less than the theoretical calligative property Okay, this you must remember in case of association the actual calligative property is less than the theoretical calligative property Okay, this is One thing. This is the formula we use to find out I Okay Correct. Similarly in case of dissociation what happens you see and then we see the formula of this Various calligative property in case of dissociation. What happens? It is exactly opposite Right. So in this you write down in this the number of particles is More than in this the number of particles is more than the expected value number of particles is More than the expected value Correct. So Similarly, if you try to find out the formula of I here in case of dissociation one example I'll write down here. Suppose the reaction is ax by and This dissociates x a Y plus Plus yb x minus This is what we get Now suppose what you need to find out here at time t is equals to zero I am considering this the concentration is a this is zero and this is zero Right, you need to find out the expression for I Try to do this first Similarly, you have to do like we have done this one for association Similarly, you have to do for dissociation Okay, so you try this once and then we'll discuss Hello Yeah, I'm taking class right now. Can I talk to you tomorrow because I have class till 10 o'clock Anything anything important to me? We'll talk to you tomorrow, okay See what we'll do here. We need to find out I so we need to we have to find out the number of particles Initially present and after dissociation that is what we need to find out the number of particles Dissociation correct So the reaction I have given you concentration I have given you Try to write down the concentration of a and b after dissociation and Then you have to add those and take the ratio initial and final done anyone Anyone has got I expression see what we have to do here a Dissociates correct So what we can write we write here at time t is equals to t will get a minus a alpha and One gives x so we'll get here x a alpha and Then y a alpha that is what we get because one gives x so a alpha gives x a alpha one gives y so alpha gives Y a alpha Correct now I is equals to what I is equals to what you see Total number of particles after dissociation, which is a minus a alpha plus x a alpha plus Y a alpha divided by The number of particles initially present a again. You see this a will get cancelled here and I is equals to we get here one plus One plus x plus y Minus one into alpha This is what the formula of I will get here x plus y is the total number of particles now suppose if x plus y is equals to n I am assuming then I formula is one plus n Minus one into alpha and this n value is always greater than one Hence I for dissociation also greater than one So it's actual colligative property is greater than the theoretical colligative properties Got it x plus y into one minus alpha You won't get you see you try to pretty you try to write down the expression. You'll get it pretty got it. Okay Again, you see one thing here for Strong electrolyte What is the alpha value for a strong electrolyte? If we have a strong electrolyte? What is the alpha value? Tell me guys the alpha value of strong electrolyte anyone the value of Alpha for a strong electrolyte Yes, one right, so Strong electrolyte alpha value is one correct This you should know first of all suppose example. I am taking any two SO 4 Right. So this any two SO 4 dissociates like to any plus Plus SO 4 2 minus. This is how it dissociates. So x plus y value is what? 2 and 1 x is 2 y is 1 right so x plus y value is 3 here Because this is x. This is why Right, so I value is what because this isn't takes place. So 1 plus x plus y Minus 1 into alpha. So if alpha is 1 if you substitute here So I value is nothing but x plus y which is nothing but 3 So what you need to keep in mind that in case of strong electrolyte? I is nothing but x plus y I Is nothing but x plus y? Got it. Okay for weak electrolyte the information will be given Right for weak electrolyte the information will be given so that you can find out Okay, that you don't have to worry. Okay. NACL if it is there. Can you tell me the I value for NACL? NACL is also a strong electrolyte The I value of NACL is what? Got it Yeah, I value is 2 I Value is 2 here because NACL dissociates like NA plus and CL minus This you should know actually for a strong electrolyte alpha value is 1 okay now you see coming back to the The all thing that we have here That what is the formula of colligative property or abnormal colligative property? Okay, so for all these things you see you need to write the formula as The first colligative property, I'm sorry the first colligative property is The RLVP relative loading in vapor pressure and for this the formula is what? Delta P Delta P by P naught a Is equals to XB is the formula right? XB is the formula, but when you have Abnormal colligative property it means when you have Electrolyte present as a solute or Electrolytic solute if it is present Then instead of writing down this you should write down here I into XB point of factor I This is the formula of RLVP Okay, delta TB Elevation in boiling point that will be I into KB into M. I just we have to introduce Delta Tf Delta Tf is equals to I Kf into M Okay, and the osmotic pressure pi is equals to I CRT This is what the formula we have when the Solute is electrolyte only just you need to put item over there understood Got it all of you now write on some questions. So what I'll suggest you here all of you guys You try to memorize this formula only what else I just you don't memorize pi is equals to CRT You write this formula, you know always you write pi is equals to I CRT okay, if the solute is Electrolyte then we'll calculate I according to the formula we have dissociation association if it is non-electrolyte then I value is 1 Okay for non-electrolyte The solute is non-electrolyte The I value is 1 and that you substitute 1 you'll get the previous formula Okay, so what I'll suggest in general what happens that in hurry We forget to write down this item in this formula So the best way is to memorize this formula only Depending upon the solute whether it is electrolyte or non-electrolyte find out the value of I and substitute Like I said non-electrolyte I values 1 substitute 1 if it is electrolyte then on depending upon association or dissociation Find out I and substitute