 Okay, so next you write down hydrolysis of salt of, hydrolysis of salt of strong acid and weak base. Can you write this expression? Similar. Similar. Salt of strong acid and weak base. I'll write down the reaction here. Salt of strong acid and weak base. The reaction is what? We can take HCl plus NH4 to H is the weak base. The reaction is reversible or irreversible? Reversible. Reversible. Reversible. Because hydrolysis is possible. That's a weak state. That's irreversible. It is NH4Cl plus H2O. What are ions we'll get here? That is NH4 plus and Cl minus. So an ion of strong base and an ion of strong acid. Cl minus is an ion of strong acid. So for this hydrolysis is not possible. No hydrolysis. And only this will go under hydrolysis. So the reaction for this is what? Plus H2O. It forms NH4OH plus H2O. So it is acidic in nature the solution is. Tell me the expression for pH for this? Similar. See instead of KA you'll get KB over there because the base. So base hydrolysis will assume as KB not K. So this is going to be 7 minus half PKB plus log C. Which one? pH? Yes. It's actually P over H here becomes pH over there. Instead of PK we'll add PKB over there. I won't derive this expression for pH will be. It is an acid solution so it must be less than 7. 7 minus half of PKB. Plus log acidic solution. pH over H is 7 plus half of PKB plus log C. Last one write down. So one minute. Done. Write down hydrolysis of sort of weak acid and weak base. Weak acid is CS3, COOH, weak base is NH4OH. CS3, COOH, CS3, COOH minus and NH4 plus. Both will go under hydrolysis. Reaction is what? CS3, COOH minus plus NH4 plus plus H2O. It gives CS3, COOH plus NH4 OH. So this concentration is C into 1 minus H, C into 1 minus H. This is CH and this is CH. What is the CH for this? Concentration of CS3, COOH. Concentration of NH4 OH divided by concentration of CS3, COO minus and NH4 plus. If you multiply H plus here, it becomes what? 1 by K, if you multiply OH minus here, it becomes 1 by KB. So H plus and OH minus, this becomes what? KW. Okay. So the expression of CH is what? KW by K into KB. This expression becomes KB. Or weak acid and weak base, strong acid and strong base. That also will be same. Concentration of NH4 plus and CS3, COOH minus is same. So that expression is coming from the same one. So that also you can write same. Concentration of H plus is what? KA is equals to, can we neglect 1 minus H? Concentration is KA into H by 1 minus H. So H by 1 minus H, you are directly substituted as this. You know that K is CSC. We need to find H plus concentration of 40 H. So let us first write down that expression for K. Is it clear? Okay. 1 minus H, here we are not selective because we need the value of H by 1 minus H. That we can directly substitute as root over of KW by K into KB. Okay. So the concentration of H plus is what? KW by, which is KA into KW divided by K. Expression of Ph is equal to minus log of H plus is equals to minus half of log A plus log KW minus log KB. Okay. If you take this minus sign inside, then it becomes half. Minus log of K is what? PK minus log of KB is what? PKB plus this of log 10 to the power is 14. Okay. Minus log of KBK, this minus as it is minus log of KB. PKB and plus minus log of KW, KW is 10 to the power minus 14. Okay. So this becomes what? 7 minus minus of plus? 7 plus K. 7 plus half of PK minus PKB. Is it right? Okay. So this does not depend on C. It is independent of the concept. No, it actually depends upon both. Accident based, it depends which one is stronger. Like further also we can proceed. From this example we cannot say pH is greater than 7 or less than 7 or equal to 7. That is only possible when you know the value of PKB and PKB. If PKB is more than PKB, right, then it is less than 7 means? Accident. When PKB is more than PKB, greater than 7, basic, but it is equal than yourself. So when you have weak acid and weak base, it depends upon the relative strength of acid and base. Okay. So there are three possibilities here, right, on the pH expression, general expression is this. Case one is what? If acid is stronger. It means what? It means KA is greater than PKB. KA is what? Less than PKB? Minus stronger. PKB is less than PKB? It means? PKB minus PKB is? Less than 0. It means pH is what? Less than 7. And less than 7 means acid is stronger. Which is true also if acid is stronger that dominates the base and the solution will have acidic behavior, right. POH is what? Base is stronger. What we can write? Greater than 0. Base is stronger, no? So KB is greater than K. So PKB is? Less than PKB. Less than PKB. Is it? What do you mean? PKB minus PKB. PKB minus PKB. Both are equal. So in this case pH is greater than 7 and POH is less than 7. The solution will be? Basic inclusion. Okay. Which whatever is strong base or acid that will be the nature of the solution. Third case is what? When K is equals to KB. Equal strength. In this case PKB minus PKB is? 0 and pH is equals to? 7. Solution will be? Newton. Write on the question. Calculate the pH of the solution. Calculate the pH of the solution. Form by mixing. 100 ml of first question. Form by mixing first question. 100 ml of 0.1 molar CS3 COOH. 100 ml of 0.1 molar CS3 COOH. And 100 ml of 0.1 molar NaOH. 100 ml of 0.1 molar NaOH. Second question. 100 ml of 0.1 molar NaOH. 100 ml of 0.1 molar NH4 OH. And 100 ml of 0.1 molar HCl. 100 ml of 0.1 molar NH4 OH. And 100 ml of 0.1 molar HCl. Third one. 100 ml of 0.1 molar HCl. 100 ml of 0.1 molar HCl. And 100 ml of 0.1 molar NaOH. Fourth one. 100 ml of 0.1 molar NH4Cl. And 100 ml of 0.1 molar CS3 COOH. And 100 ml of 0.1 molar NH4 COOH. CS3 COOH. Yes. So it's a buffer solution. No. It is NH4 OH, it's not CN. Oh, that's so much. That's a lot. That's a lot. But it gets so. K value, hey, you need to answer. Yeah, that's a lot. Why are you going? I can tell you me why. Which one? I was thinking you have to push over, you're not asking. K, KB value always will be given in the course. You cannot find it. No, you will not go K with that. You're trying to find out K with that. No, with that, we will need something. Do this now. First one is 9.85. What is 8.7? What is the correct one? You don't need 100 ml. You don't need 100 ml. So there is 8.85. 8.7, 8 or approximately. Approximately. So 8.8 around you will get the first one. Third one is 7. Second one? Second one. Same as K value is given for CSPCOH. This is given for CSPCOH K value. And K means given for NH4 OH. So K has to be 5.2. Yes, that's correct. 7, right. What is the fourth one? 7. How do we do the third one? Third one is just to find out the number of milling points. Because K value is not given. So the asset and base, we can find out the number of milling points. See which one is 7. 7 is there. Method is seen at CL and NAOH. So you do not know the K and KV value for this. So we will find out NAVA for asset. And NPVV for base. Isn't it a strong asset and strong base? And they have same concentration and other holds. Directly also you can do. I am what I am telling you. If some asset and base is given and K value is not given, then what do you have to do? Strong asset means strong base. PH value will be 7 completely right. But when KV value is not KKV just given, then you can find out the number of milling points. Then you subtract this. You will see whether this one is more or this one is more. Suppose NAVA-NVV is positive, it means this gives you H plus concentration. Divide it by BA plus AB. Last class you have done this. Like this also you can find out. And when you find out NAVA and NVVV, you will see the difference is 0. It is completely neutralized. Last one is what? Weak asset and weak base. Last one is 7. Next question right now. What is that? 7. That's one awesome.