 Okay students, join in class, who are facing any issue, please let me know. So students, have you learnt some new concepts in centrum art? Yes or no? I am just asking about the chemistry. I don't know about the subject. Definitely you are learning in others also. Are you learning something new every time? In centrum art, at least in chemistry, because in other subjects, they are following some different, according to their subject, following the process. But I try to put new things every time in centrum art. So this time, I am also related to this, to find new things. So be ready for that. My students are learning just one more minute. Okay students, anyone who is facing any issue, should we start today's quiz? What do you say? Okay, that is all. Thumbs up. Stop. Should we start? So today we will have questions. I will give you, I will give you one hint what questions you are going to have. You will have questions on, you will have questions on Lewis acid, Lewis base, Arrhenius acid, Arrhenius base, Bronsted acid, Bronsted base. First of all, second thing you will have questions on hydrolysis. Hydrolysis related questions. I just want to tell, I just want to tell one thing to all of you. Hydrolysis of only those salts under hydrolysis which are formed from weak acid and weak base. Keep this thing in mind. Those who don't know this part, just remember hydrolysis only happens for those salts which is formed by weak acid and weak base. This concept will be used in two big questions. Okay, fine. So now I am going to start the quiz. Already Lewis theory, yes Lewis theory. There are three theories of acid, basis and salt. What is Lewis means? First is Arrhenius, proton, H plus donor is acid. O H minus donor is base. That is Arrhenius theory. What is Bronsted? What is Bronsted and Lewis theory? Proton acceptor is, proton donor is acid. Proton acceptor is base. Okay, and the last one is Lewis theory. Lone bear acceptor is acid. Lone bear base is base. Don't worry that I give you a picture, you will get to know. Okay, first picture is in front of you. I am starting the quiz. Don't worry, don't worry, I am starting. Okay, fine. Fine, don't worry, Arrhenius students learn something new. It's very good for you. Which of the following does not undergo hydrolysis? Na2CO3, CS3COH, CS3CO, NH4 plus K2SO4. Which of the following does not undergo hydrolysis? I gave hints because I thought that many of you don't know about hydrolysis. That's why I gave hints. Aditya, I gave hints till you don't know why. Okay, last 15 seconds. Okay, fine. Yes, yes, yes, yes. Okay, answer is D. Answer is D. Let us see how many of you have answered it right. Oh my God, after giving hints you people are making a mistake. Why, why? I just, just now I gave you a hint. And still you people are making a mistake. Okay, fine. So, I will tell you. Okay. So, fine. So, here is the question number one. Question is very easy. Hydrolysis happens for only those salts which are formed by strong base, sorry, weak acid and weak base. Na2CO3 is formed by NaOH plus X2CO3. Base is strong but acid is weak acid. So, it won't, it will hydrolyze. Okay, I want to tell what will hydrolyze, always remember. You know, this is weak acid. Weak acid always dissociates like this. I think most of you know this. Weak acid always dissociate like this. So, anion of weak acid is, if this is weak acid, anion is called as conjugate base. Conjugate base. This is called as conjugate base. Now, this undergo hydrolysis. This undergo hydrolysis. Always remember. Always remember. Anion of weak acid undergo hydrolysis. If I ask you, there is something weak base. What thing will undergo hydrolysis? If there is weak base, if there is a weak base, what thing undergo hydrolysis? Yes, metal ion or the cation, very good. Anion undergo hydrolysis in case of weak acid, in case of weak base. Let's say here NH4 plus, here your base is NH4OH. And acid is CS3COO Na, COH. This is acid, this is base. Weak base, weak acid. So, what all things we are going to hydrolyze? Tell me, I am not going to tell you now. Which all things we are going to hydrolyze in example 3? Which all things we are going to hydrolyze? Think, in case of weak acid, conjugate base hydrolyze. So, this is weak acid. What is the conjugate base of CS3COOH? What is the conjugate base of CS3COOH? Very good. CS3COO minus is conjugate base. So, this will hydrolyze. So, I will write CS3COO minus will hydrolyze. What will hydrolyze in? What will hydrolyze in your NH4OH? Don't write only NH4, it is wrong. NH4 plus, weak acid, weak base, here your conjugate acid will hydrolyze. Conjugate acid will hydrolyze. Okay, you will learn it in detail in class 11. But as of now, you can understand it like this. Here it is only acid. So, normal acid does not means it will undergo hydrolysis because what will undergo hydrolysis here? CS3COO minus. CS3COO minus, like this here also. Why NH2CO3 will hydrolyze? Because you have two things in NH2CO3. What two things you have in NH2CO3? CO3 minus is coming from the weak acid. CO3 2 minus is coming from weak acid. That will undergo hydrolysis. NH plus is cation coming from strong base. That does not undergo hydrolysis. Always remember, not all acids undergo hydrolysis. Hydrolysis always happens either for cation or anion. Hydrolysis happens either for cation or anion. Cation of weak acid, sorry cation of weak base, anion of weak acid. Only these things undergo hydrolysis. Shreyash, is it clear Aditi Shreyash? Yes. Any doubt? Now why this is the answer? K2SO4, K plus, SO4 2 minus, K plus coming from KOH, H2SO4 coming from H2SO4. Both are strong, strong base, strong acid. Nothing will hydrolyze. Is it clear to all of you? Why can't be the three? Because which among does not undergo hydrolysis? Here you have NH4OH. Now see, because both are weak, it will undergo hydrolysis. They have asked which does not undergo. CS3CO minus will undergo, NH4 plus both will undergo. Because both are a part of weak acid and weak base. Is it clear? Meghana. Meghana. Okay, please remember this part. This will come in the salt analysis chapter. Salt analysis in class 11. So if you understand this topic, that will help you. Like what all undergo hydrolysis? What all does not undergo hydrolysis? Let me take you one next step. Let me take you one next step. One last question. If this is undergoing hydrolysis, what will be the product? What will be the product if this undergo hydrolysis? Any idea? Just last. Hydrolysis means breaking the bond and forming new bond with the help of water. No, no. Okay, I will tell you. Hydrolysis of CO3 2 minus. What will be the product? Product of CO3 2 minus is H2CO3 plus OH minus. Plus OH minus. That's why carbonate, whenever there is a carbonate ion, it will give you OH minus in the solution. That's why I am calling it as a conjugate base. Because if I am using the word conjugate base, it should behave like a base. Why? How it is behaving like a base? If you take carbonate ion, in water it gives you OH minus ion. That's why it is called as conjugate base. Did you understand why people call it as conjugate base? Why we call something which is, when something, some acid is breaking, it gives you some anion. This anion is called as its conjugate base. Why? Because this conjugate base gives you OH minus like this. Is it clear to all of you? This is very important concept, that's why. Yes, yes, no problem Aditi. This is a weak acid and weak base undergo hydrolysis. Weak acid, weak base not. Anion and cation of weak acid and weak base undergo hydrolysis. Not weak acid, weak base. They are cation and anion. Understood? This is nothing but a proton acceptor. This is nothing but proton acceptor. Proton acceptor is called as which type of, which type of base? Proton acceptor is which kind of base? Proton acceptor is Bronsted and Lory base. Bronsted and Lory base are called as proton acceptor. Okay? Okay students. Could I move to next question? I am erasing all this. Okay? Yes or no? Okay fine, someone has asked one more question. NH4 plus plus H2O. Who all can answer? Please answer students. Who all can answer this question? NH4 plus H2O. Very good. NH4 OH plus H plus. That's why it is called as conjugate base. That's why it's called as conjugate, sorry, conjugate acid because it is giving H plus. That's why it's called as conjugate acid. Is it clear students? That's why we call it as conjugate acid. Hope you understood this part. Yes conjugate acids give H plus in water. Conjugate base gives, but that is the definition of acid only. Acid gives H plus ion in the acid acid, what we call as acid which gives H plus ion in water. That's why we call it as conjugate acid. Hope you understood this part. This is completely new for all of you. That's why I explained. Is it clear to all of you? Yes or no? Fine, I am moving to the next question. Now we will go little fast. Okay? Okay fine. So this is the result. Don't worry. Next question. Now you have some easy questions also. So attempt it properly. Example of conjugate acid. I told you conjugate acid is like anise 4 plus is conjugate acid. Ca2 plus is conjugate acid. And all that at the 3 plus is conjugate. All these are conjugate acids. 2 plus is conjugate acid. Okay students. Let us see what you are getting in question number 2. Okay one minute. It's not showing the result. Oops something went wrong including result. Just a minute. Just a minute students. Just give me one minute. Okay fine. Okay do you want to know the answer of that question? I will tell you answer. Answer for question number 2 is Okay. Just a minute. Fine. Question number 2 select the acid. 4 hydrogen acid is acetic acid. Ca3COOH. But formic acid is HCOOH. So those who are marked formic acid they are wrong. Understood? Okay fine. Next question. I think all of you should get it right. Organic recaster. Please answer it for our students. I look for options are formic acid, sulphuric acid, nitric acid, hypochloric acid. Formic acid. So answer is formic acid. So answer is AOH, still some have that wrong. Answer is formic acid. Okay next question. An extra solution of following components is those ions and molecules is. You need to apply concept here in which states both ions and molecules are present. Sulfuric, hydrochloric, nitric and acid. Okay last 5 seconds. The answer for this question is acetic acid. Let us see how many of you got the correct answer. Okay students weak acid does not dissociate 100%. That is its definition. Weak acid weak acid does not dissociate 100%. That's why okay fine. That's why you put the reversible sign. If you know weak acid is something like this. Okay this was the question. So you know weak acid if I draw the acetic acid. This is acetic acid. I always draw that double arrow, double arrow because it is weak acid. And it does not dissociate 100%. That's why I write like this. Cs, C0, minors and h class. But if I write hcr. You know many people write double arrow also but if you literally tell me to draw the double arrow I will put the second arrow very small. I will put the second arrow very small and first arrow very large. Why? Because mostly it's in the forward direction. So many people write it like this. Small second arrow like big first arrow. That is h class and cl minors. It actually dissociates 100% dissociation. 100% dissociation. Almost 100%. That's why in a container of hcl. In a container of hcl you will have h plus and cl minors only. No hcl. No hcl because all hcl has already broken down into h plus and cl minors. But if you have a container of acetic acid you will have all the three things. All the three things means cl minors, h plus and cl minors. Is it clear to all of you? The same thing is applicable for weak bases. You will have an ion as well as molecule. Students is it clear to all of you? Yes or no? Okay good. Next question. So now Vibhav is reading very good. Vibhav you will see Omita J is also next to you. Which one of the following will not produce acetic acid made to react with water? Think properly. You have 60 seconds. Which one of the following will not produce acid? I told you one concept like which all things are acid which all things are not acid. On putting into water what will happen? You have to predict here. This is a very easy question and at the same time you should also know the concept and apply it in other questions as well. Okay you want to... Why you want me to read there? Why aren't you? Okay fine I will read. Okay fine I will read. Okay fine. Answer for this question is carbon monoxide. Carbon monoxide is a... Oh my God. Only 11 students have done this right. Okay fine I will explain. Wait wait wait wait. The options are wrong. Okay V is here. One minute one minute. Don't worry. I will change it. Carbon monoxide is the answer. Answer is A. Okay fine I will change it. Okay I will change it. Carbon monoxide is neutral. Carbon monoxide is neutral. Okay it is neutral. And rest all are carbon dioxide is acidic. All non-metallic oxides are acidic. Acidic acidic. If I give you... I know also acidic or neutral. It's also neutral. Okay I will change the answer students. Just give me one second. I will change the answer. Fine question number 5. Answer is A. So... Question number 5 answer is A. Just a minute I will change it. Question number 5 answer is A. One, two, three. Okay I have already changed it. Don't worry. Now you all get no room. Okay students. Don't worry I have changed it. Now I am going back to the presentation. Yes yes I am sharing my screen. So you can see screen now. Okay so students. Here you can see the... Okay just a minute. Okay so here. So this is the next one. We are ready for the next question. Now you can see I have changed the answer. Okay students. So this is your score leader board. We have always leading. I think all of you can see your scores now. Okay next question is in front of you. Matter oxide which can react with acid will give alkali is. Matter oxide which can react with acid as well as alkali is. I don't think this question is very tough. Okay Arya you must have missed it. Okay no sir it happens all the time. Okay with few of you maybe. Okay student answer for this is aluminium oxide. Aluminium oxide is amphoteric in nature. So I think most of you got it correct. Aluminium oxide amphoteric oxide reacts with both acid as well as base. Could I move to next question? Yes okay fine. Oh we both this time we both have not performed good. We both what happened? You don't know about amphoteric oxide. Okay fine next question. Okay fine during ionization metals lose electron. This change can be called ionization metal lose electron. This change can be called oxidation reduction redox displacement. What is ionization? If you understand that then you can also answer this question. Okay last 15 seconds. You know this is very easy question and this will give you the clarity of concept. You know answer is oxidation whenever any metal lose electron. That is called as oxidation. Gain of electron called as reduction. Ionization is something when you remove electron from some atom that is called as oxidation. Very good oil break. Oxidation is loss of electron. Sir what is what about auto ionization. Whatever ionization means loss of electron that's it. Understood next question. Okay you want to see the reason for it. Okay now fine. Now very good momita, abitsa, liver, momation. Good. Check it out. Next question. A salt in the solution gives a pale green precipitate with sodium hydroxide solution and a white precipitate with various chloride solution. A is ion free sulphate, iron free sulphate, iron 2 chloride, iron 3 chloride. Please don't make mistake in this question. I didn't see chloride and sulphate. How? How come you... So what you are saying iron 2, iron 3 that's it. Very good, I think you are very good. Yes. I just want to know how many of you remember this one. That's why I have added this question. Okay fine. So the answer for this question is, is B. Okay some are saying B. You see B is the answer. Barium sulphate is white precipitate. Aphid 2 OS volt twice is green color precipitate. Generally salt of Aphid 2 plus R green and barium sulphate is white. There is nothing called so close. Either it's right or wrong. Okay. So here again, Momita is reading good Momita. Next question. Always remember iron 2 plus 2 salts are generally green. To increase the pH value the removal solution we should add. My dear student, please see the time. This question is very tough. I know that. So please see the time. Okay. Answer is C only. To increase the pH. To increase the pH add base. To decrease the pH add acid. Salt is not always true. There are some salts which are adding increases the pH or decreases the pH. But it is not, you can't generalize it. Yes. Okay. Fine. Moving to next question. Are you all ready? Okay. This time. Okay. Fine. Question is also there in the list. Okay. No change. Fine. So be ready for next question now. Which of the following is not the base according to any of the theories? You have 1 minute 30 seconds. Please think about the three theories which I told you. Which of the following is not a base according to any theories? Please take your time. Any theories? Not a base. How do people misclick? So why you are so in so hurry? I told you please read the question carefully. You have next and next question. For some people you have 20 seconds. For some you have 120 seconds. To think about the time. But see the time and then attend the question. Okay. You have 30 more seconds. Why you have put it is the most sensitive. Please reduce the sensitivity. It is just kind of hidden trial method. So. Fine. Last 5 seconds you have. Okay students. I think you all got the answer. First we will see the leader that answers. Okay. How many of you got it correct? 34 students got it correct. Because nothing but question number 10. Yes. Now. Those who don't know the answer for them. I am explaining. MG OH4 twice. When it breaks. Gives you MG2 plus plus OH- It is 2 times of OH- It is base. But which kind of base? Arrhenius base. Arrhenius base because OH- It is giving out. Right. Giving OH- Giving OH- That is Arrhenius base. And second kind of base. Arrhenius one is. Okay. Fine. Arrhenius base. Now. Coming to the next one. Ammonia. Ammonia is. Ammonia. If you give H plus. It will accept H plus. Proton acceptor. Proton acceptor are called as. Proton acceptor are called as. Bromstead and Loewe base. Okay. Proton acceptor are called as Bromstead and Loewe base. At the same time it has lone pair also. Ammonia has lone pair. So it is also called as Loewe base. I am telling all this. It is not required in this fiction. But with the help of this fiction. I want to clear all of your doubts. I want to know the base as well as it is Loewe base. Because it has lone pair. Okay. Fine. H2PO4- So in no case it is an acid. Okay. Not base. Okay. It is base. H2PO4- Now if you see H2PO4- Where it breaks down. It gives you. H2PO4- Plus H plus. So it is actually an acid. It is Arrhenius acid. It is Arrhenius acid. As well as it is Bromstead and Loewe acid. Always remember. Bromstead and Loewe acid and Arrhenius acids. Are same only. Whenever you get the Bromstead and Loewe acid. You will definitely get that as Arrhenius acid also. Okay. Vf3 exists. Yes my dear. Vf3 exists. Okay. So this is Bromstead and Loewe acid. And so fine. Now coming to the last option. Vf3. Vf3 even means it exists. It exists. But if you all know that boron has 3 electrons in outer monstead. What is the atomic number of boron? Atomic number of boron is 5. 2,3. It has 3 electrons. It forms bond like Vf3. But now its octet is not complete. 1, 2, 3, 4, 5, 6. So it is octet is not complete. So it will accept lone pair. Accept lone pair. So if it accept lone pair. If it accept lone pair. Then it is called as. Which base? Which acid? Yes it is an acid. Which acid? Accept lone pair. Which acid? Just see here. Lone pair donor. When it is a lone pair donor. It is a Loewe's base. When lone pair accepted. Loewe's acid. Again I am repeating. Loewe's acid is something which accepts lone pair. And base is something which connects lone pair. That is Loewe's concept. 3 concepts are there. Arrhenius, Bronsted and Loewe and Loewe's. How I remember? Arrhenius A is the first letter in alphabets. So it is the first theory. First theory was totally based on H plus and Loewe's minus. H plus donor is acid. Loewe's minus donor is base. Then B comes after A. Bronsted and Loewe. It is totally based on H plus and H plus. H plus donor is acid. H plus acceptor is base. And L stands for. I remember it like this. L for lone pair. So lone pair donor and lone pair acceptor. This is my way of remembering or acceptor. You can make your own technique. Own trick. You know why C is correct? Which of the following is not base? Okay fine it is acid. But it can act as base also. How? H2PO4 minus can accept the H plus. And form H3PO4. Then it is a base. It can act as base also. Understood? H3PO4 minus can act as acid. It can act as base. No no no. This is H3PO4 is acid. But H2PO4 minus you have H2PO4 minus here. H2PO4 minus. You have H2PO4 minus. It is H2PO4. I think you can all can see it is H2PO4 only. H2PO4 minus accepts proton yes. And it can loose proton also. It has both options. It can accept as well as it can loose. Understood? It can do both. Am I clear? To all of you. Sure. This is one question which I wanted to explain in detail. Be concept. Arrhenius, Bronson and Lourie and Lewis. According to which theory it act as base? Very good question. Who can answer this part? According to which theory it can act as base? Yeah. Bronson and Lourie. Because it accepts proton. Because it accepts proton. Understood? Understood. Can accept and Lourie right? Yes. So it is Bronson acid also and Bronson base also. Isn't it interesting for you to know that H2PO4 minus can act as acid. Can act as base. Bronson acid also and Bronson base also. Is it clear to you? To all of you? Yes or no? Sure. I am moving to the next question now. Hope you have copied everything whatever you wanted to copy from this part. Or whatever you have found it. Whatever you found new. Sir what is Arrhenius theory? Arrhenius theory is H plus donor is acid. O H minus means what is Arrhenius theory? When some compound H plus solution of any compound which gives H plus ion is acid. H plus solution of any compound which give O H minus is base. That is Arrhenius theory. Is it clear to all of you? Could I move to next question? Yes or no? Two switch. What is two switch? I didn't understand. Six in three two one eight. Next question. Very good. So here this time. Here students. Any problem in this? You have fifty more seconds. I have explained you Lewis acid base theory in detail. And not just Lewis acid base. All the three theories. Now I hope that you understood the theory and you will apply it in this question. I think I am not muted. Am I not audible? Students can you hear me? Okay fine. So we will see this question how to do. So question yes. This is the question. According to Lewis acid base concept which is the correct statement? The species in which central atom has completely opted cannot act as an acid. Okay. That is the correct thing. Lewis acid base theory means lone pair. Lone pair acceptor. Okay. Lone pair acceptor. So if it is already having a complete opted it won't accept. Yes yes I will come to that. Why answer of why three is wrong? Molecule in which central atom has vacant the orbital act as acid. Yes it is true but not always. In BF3 there is no vacant the orbital. But still it can act as acid. So in which the molecule in which the central atom has vacant d orbital x as an acid. But not always true. One is always true. Vacant d later you will understand. Vacant d orbitals like orbitals which is d sub cell later you will learn spdf. So the d sub cell is there if that is vacant they will act as an acid. But it is not always true. It is not always true. Okay. If you talk if you if you ask me PCL 3 PCL 3 is also having a vacant to d. But it does not act as acid. It does not act as acid. So it is not true. Answer is A. Next question. One minute. It's base what what Ananya please ask your doubt. What Ananya what it's base means. PCL 3 no it's nothing it's all that's it. Okay. According to Lewis theory neutralization is the transfer of proton from acid to base. Transfer of proton from base to acid. Transfer of electron pair from acid to base. Transfer of electron pair from base to acid. Lewis theory we have discussed in detail. So I hope all of you can answer that question very easily. And transfer of electron pair or transfer of proton from acid to base. What is the Lewis theory. Okay. Neutralization according to Lewis theory lone pair donor is base. Lone pair donor is base. Oh my God. Answer is D. Students why you are making mistake. Okay. See I'll tell you nobody. So this is the question. Right. Understand. Okay. Question is this. Don't worry. I'll explain. According to Lewis theory. Neutralization is I told you Lewis theory is Lewis theory is lone pair donor. Lone pair donor is base. Lone pair acceptor is acid. So transfer of electron when neutralization takes place. So lone pair will be given by base taken by acid. Transfer of electron pair from base to acid based answer. Is it clear? Is it clear or not? Yes. All of you. Fine. No. So you know there is one type of neutralization you can't you can't think of also. NS3 and BF3. It is a Lewis. Can you think what is the product? Can you think what is the product of it? No. Transfer of proton is nothing from acid to base is the Bronsted and Lory concept. BL concept. What is the reaction of NS3 and BF3? It is Lewis acid. It is Lewis base. You know the product will be this lone pair will be donated to BF3. So formula of that compound is like this. Later I will explain in class 11 to all of you. This is the BF3. I write like this. NS3 coordinate bond BF3. This is the salt. This is actually salt. This is the nothing but coordinate bond. You must have heard about coordinate bond. Yes or no? Coordinate bond only forms when there is a lone pair of electron. Coordinate bond. Coordinate. Okay. No worries. No worries. But you know this reaction also takes place and it is a neutralization. Is it clear? Is it clear to all of you? I am moving to the next question. No, NS3 does not convert it into BF3. NH3 donates its lone pair to BF3. There are 3 fluorine atoms in boron. In boron 3 fluorine atoms it has a vacant orbital. It is donated. It is same reaction like NS3 is donating its H plus and NS3 is donating its electron pair to H plus. So you will get NH4 plus. It is the same reaction like this. You know how we can write this? Please mute your mic all of you. How we draw this? We draw it like this. H plus. Okay. I will mute it. Okay. So this is a structure of NH4 plus. Lone pair donated to H plus. That is the NH4 plus. Understood. If someone wants to know what is NH4 plus it is drawn like this. Similarly I have drawn BF3. NS3 dot BF3. NS3 dot BF3 is nothing but NS3 donated its electron pair to BF3. Same like NS3 donated its electron pair to H plus. Is it clear? What happened Ananya? Any doubt? Ananya Ananya any doubt? No sir. Okay fine. Moving to the next question. Okay we will see the leader goes first. Okay today result is very much like I mean every question the result is fluctuating too much. I am not saying the talkers earlier who were talkers now they are not in the front page. This means that okay now this just see this question carefully. Spectator ion. Spectator ion when you see in your life and when you when you heard this term if you remember then you will get the answer of this question. And hydrolysis. Hydrolysis of this is done. Write the spectator ion. Spectator ion for your information I want to tell because 25 and 27 have already answered. Spectator ion is something which does not change. Which does not change during the reaction that is called as spectator ion. I would like to see how many of you get this question right. I want to see that. Spectator ion in this question. Spectator ion is something which does not change during the reaction. Okay Jai Matadi. Yes see how many of you are going to get correct. Okay so answer of this question is 15 of you got it correct. Very good students. Very good. My dear students spectator ion is something which does not change in reaction. I told you hydrolysis will hydrolysis will happen for anion and cation which come from weak acid and weak base. Which comes from weak acid and weak base NH4 plus comes from weak as weak base comes from weak base. Comes from weak base. Okay and CO32 minus comes from weak acid comes from weak acid. This means that these both will undergo hydrolysis. If hydrolysis is happening let's say I put NH4 plus plus water. So there is now you don't get NH4 plus you will get NH4 OH plus H plus. So actually your NH4 plus 4 undergone change and become NH4 OH. So this is not the spectator ion. Spectator ion is something which does not undergo change. That is a spectator ion. If you remember if I write CaOH whole twice plus HCl will give you CaCl2. CaCl2 plus water as a liquid. So here calcium is plus 2 and here calcium is plus 2. Both are spectator because it does not undergo any change. So we will cut this. Yes. Which does not undergo change. I will write this reaction again. CaOH whole twice aqueous plus HCl aqueous gives you CaCl2 aqueous plus HCl liquid. HCl liquid sorry H2O liquid. Now in this case calcium plus 2 is spectator ion does not undergo any change. Cl minus is spectator ion. So final thing final ionic equation left with you is OH minus plus H plus give H2O. Why you are not getting H plus and OH minus? Because water is in liquid state. Water is in liquid state I told you whenever something solid and liquid forms you don't cut them that are not spectator ion. Hope you understood this. Yes or no. Next question. Okay. Next next question is in front of you. Which of the following records both Bronsted acid and Lewis acid? Think 60 seconds you have both Bronsted acid and Lewis acid. Bronsted and Lewis acid. Okay. Bronsted acid is something which donates H plus only option was D only option was D because it can only donate H plus NH4 plus none of them had H plus none of them had H plus so answer will be D is it clear? Last question what happened Aditya NH4 plus Bronsted acid which donates H plus copper 2 plus No copper 2 plus context because it does not have H plus. Okay. Why not SO2? SO2 is also not having H plus in that. That's why. Okay. Last question. We'll see the leaderboard first. Okay. Last question. Which of the following does not show acidic nature? Acidic nature. Which of the following is cannot be cannot show acidic nature? H2CO3, CaCO3, HCl and Hs of 4 minus. Hs of 4 minus cannot show acidic nature. Answer is CaCO3. CaCO3 is the answer. Okay. Good. Most of you got the answer. Students any doubt? Any doubt? No doubts? Fine. We'll see the result of today's quiz. Congratulation Prishan. Congratulations. Okay. Ask that if someone asked conjugate acid and conjugate base. There is nothing but like if you have NH4 over H. So this is base. Base has a tendency to do over H minus. Whatever other things you are going to get. That is it's conjugate acid. Is it clear? Is it clear to you? Congratulations to all those students who are under 5. Lux, NPS, Pranav, Vipsha, Momita, Ananya, all of you. Okay. Is it clear to all of you? NH4 plus and RUX minus 10 plus. Okay. Someone asked this. Ananya. Ananya. Is it clear? No. Ananya. Is it clear? No. Ananya. Ananya. Ananya. Ananya. Is it clear? Ananya. Spongidate acid. This is conjugate acid only. Ananya. Right. When you have a base that will, whatever the cation it will form. That is a conjugate acid. Understood? Let's say you have HCl. Let's say you have NaOH. NaOH can break. It will form NH4 and OH minus. This is a conjugate acid. Understood? Base and base. Whatever cation it will form. Other than OH minus is a conjugate acid. Okay. Any other doubt? Okay students. Thank you. Hope you learned something today.