 Okay, then fine. I'm going to start now. So get ready. The first vision is in front of you With change is an oxidation Fe O 2 Fe 2 O 3, Fe 2 O 3, 2 Fe O, H 2 O 2, 2 H 2 O, and H 2 O 2, H 2 O With change is oxidation. Yeah, 70 students have already answered. Yes, you need to do it fast But it's not at the cost of wrong answer. The right correct answer only. Yes, I think Who has not answered? Of course, sir, have you answered? Okay, fine So most of you have given the right answer. It's the first option a only so because if you see Okay The answer is Fe 2 O 3 only. So how to check? Fe O you have you got Fe O and it was forming Fe 2 O 3 So one if you go with the oxygen one iron is having one oxygen Okay, now one iron is having 1.5 oxygen. You can go like that also. Otherwise the best method it is mine minus 2 plus 2 Okay, it is plus 3 minus 2 change in oxidation number is for increase in oxidation number is increase in oxidation number increase in oxidation Okay, so next question so Meghna is leading now Let's have the second question Which statement describes what happened in the reaction shown? Carbon and magnesium both are oxidized Carbon is oxidized and magnesium oxide is reduced Magnesium is oxidized and carbon dioxide is reduced Magnesium oxide and carbon dioxide are both reduced Thank you sir. Have you answered? Okay, still 3 are wrong still 8 9 10 students are wrong. Okay, so answer is Very easy for this question. If you see the okay first see the leaderboard Hi Anushka is leading now. Oh, Surya P. That is it That was the fastest to answer this. Okay to explain this you have MGO and You got the CO2 Reactive with it. So what will happen? Magnesium one minute You Did we have magnesium or magnesium oxide? Magnet I think magnesium is there. No, so it will give you mg MGO magnesium is getting oxidized and carbon is getting reduced Yes mg plus CO2 mg plus CO2 yes mg o n so it is oxidized and it is reduced Okay, so now next question. So one is oxidized means other is definitely getting reduced You can go with the oxidation on the record. So in which case oxidation is taking place Okay, Neha now you can't join Because the quiz has already started once it gets started you can't join. Okay. I've already done that. It's fine No, anytime anyone can join as of now. We have not kept the window locked So when you enter the code they can join Okay, sir. Okay. Yeah, okay one more student For 49 are right, but still 23 4 and 4 So there are many many of you answered it wrong. So let me tell you the answer Answer was the D option. Now. What was the question? Was very easy to see the vision is saying that which among the elements of vanadium Which is oxidation taking place vision was given the O2 is converting into V2 O3 Okay, and next option was V2 O5 converting into the O2 Why you people I made mistake in this V2 O3 is converting into the O and the last option was V2 O3 converts into V2 O5 Okay, see the oxidation number if you see the oxidation numbers it is like this Oxygen is minus 2 Yes, so plus 4 and minus 2 what else now here Here it is minus 2 Oxygen is minus 2 so accordingly to balance that it is plus 3 so it is reduction Vanadium is going from plus 4 to plus 3 it is reduction Okay, similarly you do partners it is plus 5 oxidation number it is plus 4 again reduction If anyone is facing any issue, please let me know Oxygen is now here if you do the crisscross it is plus 3 and it is plus 2 Here also if you do crisscross plus 3 Here it is plus 5 the only option where oxidation number increases this it is the oxidation I hope you got the answer Okay, next Any doubt Okay, don't write yes if anyone has any doubt just write something or n something like that Okay, fine next question Next question Which of this reaction lead oxide is oxidized? Try to give right answer. We have discussed this question. So don't make a single mistake Okay, still six students have made the not seven students have made the mistake fine. The question was very easy Okay, first see the leader board leader board says that Surya P is still leading and fastest was Sanjeev good So again, it was just the question related to the lead oxide in all the three cases lead oxide was converting into lead You can directly say In all the three cases the DC it was converting into lead, but in the last option it was going to pb o2 d option So if you see here, it is plus 2 minus 2 0 So plus 2 lead is going from plus 2 to 0 Reduce in oxidation number is reduction and Here it is 0 2 here. It is plus 2 2 plus 4 so it is Oxidation Okay The red color is some pottery glazes may be formed as a result of the reaction shown co co And co2 and for the co reacts with s and o this equation shows Yes Oxidize and two is reduced with substance correctly complete the gas Uh Complets the gap one and two in the above reaction So 55 I've already answered fine Oh mixed answers Fine. So answer is the only now. Let's have a discussion on this One is oxydives and other is getting reduced. So See in last class. I also told you now see many of you may get confused with the first reaction That was co co 3 converting into co o Plus co 2 you know in this reaction if you say which is oxidation which is reduction if you got confused I also don't know what will happen. So what I will do I will see the oxidation number So what how to see the oxidation number? You know that copper sulphate is formed by copper carbonate is formed by Cu 2 plus and co 3 2 minus by crisscross Definitely it is plus 2 Now carbonate carbonate is co 3 2 minus. I don't know about carbon. I consider it as a x So I don't know oxidation number of carbon. I have considered it as x Oxygen is nothing but minus 2. So how to calculate the x? I know the overall compound is neutral If it is overall neutral means net charge is 0 net charge is 0 If net charge is 0, I can write 2 times plus x Minus 2 into 3 because the oxygen atoms are there So this is 0 implies x is nothing but plus 4 x is plus 4 Once you get x is plus 4 means I will write here. It's plus 4 Now if you see copper it is still plus 2 minus 2 Okay, do here oxygen is minus 2. So there are two oxygen minus 4 this carbon must be plus 4 This carbon must be plus 4 Uh, I don't know. Let's talk. Okay. So now so so this is Actually, there is no red ops reaction in this copper retains its oxidation number every atom retain its oxidation number. So No change in oxidation number. So it is not a red ops reaction Okay, so this means that everything is there in the next reaction only. What was the next reaction for? Next reaction was c u o converting into We reacting with s and o converting into c u plus s and o2 So if you go with the oxygen transfer you can directly say which is oxidized which is reduced If you want to go with the red ops oxidation number plus 2 minus 2 plus 2 minus 2 Zero neutral atom is element is always having zero oxidation number Plus 4 minus 2. So s n is going from plus 2 to plus 4. This is oxidation Copper is going from plus 2 to 0 reduce in oxidation number The copper is going from plus 2 to 0. It is reduction. So this is the answer C u s last option was s and o is oxidized. Yes, s and o is oxidized Okay, next question Okay, any case in past tense very good. Okay, but still you have to think you should Don't make mistake take your time and write the correct option Just a minute. How it goes Okay, I think it's a repetition of question Okay, just mark the correct answer. We have already done this but no problem mark the correct option Oh, sorry option is given hydrogen is not a metal but it has been included in the reactivity series because it The photo is wrong. Don't see the photo question is hydrogen is not a metal But it has been included in the reactivity series because it Look at the options hydrogen is not a metal but it has been included in the reactivity series because it pick is wrong but just see the options yes what you learn from this question those who have answered just without saying because they want to answer it fast you should read the options also I think options are visible to you okay 52 of you are right only 18 students mark it wrong because they have not read options properly maybe some of okay so answer is a because hydrogen is also showing a character like a metal it loses electron like metal loses electron how if I take sodium sodium lose electron like any plus it form any a plus plus e similarly hydrogen says okay hydrogen takes the same thing H plus plus so hydrogen forms that's okay though it's a it forms by H2 only to H plus plus 2e but it shows the that's why it resembles the alkali metal okay so read the question properly okay now next question so next question is in front of you reactivity of iron magnesium sodium zinc towards water are in the following order select the correct answer reactivity of iron magnesium sodium and zinc towards water in the following order three of you are not answered I'm sorry okay take your time but don't make a mistake 51 of your answer 58 of your answer right good so there is a one you know there is a reactivity series and I generally tell one trick to students those who don't know they can remember the trick for the reactivity series what is that please stop calling me stop calling me careless careless yes zombie instead instead try learning how creators mercy how creators mercy saves mercy saves green planet saves green planet okay so what is please people please is potassium a stop is sodium calling is calcium okay so stop calling me is magnesium a is aluminum careless is carbon remember this is a non-metal I have added here okay zombie is zinc instead is iron try is thin try is thin learning is led how is hydrogen it is also non-metal creators is copper mercy is HG saves is silver green is gold planet is planet is platinum okay so this is a trick you can remember okay those who are wondering why sir has added carbon and hydrogen in this because if you see carbon can reduce all of these carbon can't reduce all of this that's why to exception in exception of a metal from its old we don't use carbon for these metals we can use carbon for these metals for extraction of or for reduction so what can I say carbon cannot reduce all these carbon cannot reduce so this this group carbon cannot reduce that's why I have added carbon in the series okay so and you know that reactive metal displaces less reactive metal from its salt so if you have a zinc oxide plus carbon you can easily get zinc plus you but when you have a year two or three plus carbon you won't get aluminum plus you okay so that's the reason and this is in front of you it is very important series okay thank you so yes Anikai tell me what Anikai do you want to say something okay fine so this will help you a lot that's why I have told you my student okay fine so next question yes now answer this take some time don't answer it so fast I can't see question question is which of the following nitrogen oxides is that anhydride of HNO2 which of the following nitrogen oxides is that anhydride of HNO2 question is options N2O NO2 N2O3 and N2O5 options are in the fission itself you can see options are in the fission okay so answer is oh my god answer or see and you okay fine so just see the question the question was very easy HNO2 not very easy but still it's a good question HNO2 there are the anhydride anhydride means when you remove water from something you will get the anhydride okay then someone say okay sir how to remove water it has only one hydrogen if you want to remove water you have to subtract H2O but it has only one water fine make take two molecules of HNO2 HNO2 and HNO2 take two molecules if you remove water from this what you are going to get remove water means two H you will remove nitrogen R2 and 2 O3 this is anhydride is it clear to all of you yes what is the anhydride of let's say HNO3 what is anhydride of HNO3 what is anhydride of HNO3 very good so you can do like that understood it is to take two molecules of this and subtract water it will pump N2O5 okay fine next question which of the following is true okay don't see the image just see the option just see the options and question which of the following is true don't see the image which of the following option is true color of basic copper carbonate is green Merachite is an ore of copper aluminum is more reactive than copper all of above don't see may just try to see the options and select the best option no option again why option I told you that copper is color of basic copper carbonate is green Merachite ore is copper aluminum is more reactive than copper why you have done that when I told two three times why you have answered for the pick if I told you to go for the option which of the following is okay so answer most of you are given the 39 okay the question was all the options were correct okay Merachite is a ore of copper basic copper carbonate is green in color so all the options were correct okay yes it's taking random options so just repress refreshing will maybe okay you can repress it and join it I think okay don't refresh okay next which I am showing it to you okay it will not let you join again so don't repress it okay it's a mixed opinion so you can repress it I think you can repress it okay repress it and join so all the four options were three options were right in the previous question okay next question okay please ignore it got submitted by itself okay okay sorry it got submitted by itself sorry for that sir I'm seeing only terms and conditions okay yeah I'm not a huh comes and conditions after the question nothing are you not able to see the question then aditya what's your name yeah huh aditya you just need to you know kill that browser go to a new browser type menti.com and type the code you will be able to do again okay sir sir just okay okay the question I am reading in front of you there is some problem in this but what is the question which of the following method is suitable for preventing iron iron flying pen from rusting so you apply the zinc coating in that okay applying paint will not work and applying grease will not work to have a zinc coating so that you can feel it is on the rusting okay this is a question but you will okay they are moving to the next question just let me see your name okay question I am reading in front of you which of the following matter will not display hydrogen from steam dilute acid and alkali iron zinc mercury and calcium okay we don't use paint because there are chemicals when you heat that they may that things may be volatile in nature so that is not good for and it will mix with the food which we that's why we don't put paint okay please don't chat if you have anything related to question then only you can talk which of the for see now the question was which of the following will not displace hydrogen from steam dilute acid and alkali so then from steam dilute acid and alkali so see okay zinc will displace most of you have written the mercury as answer zinc is more reactive than hydrogen yes zinc is not the answer at all okay so but which will not displace hydrogen from steam and alkali so alkali you know okay we'll come to this question again I think answer put is wrong here so we'll come to this question again okay move to the next one we'll discuss this okay leave this question okay so next question please solve this question okay so see most of you are made mistake in this question the question was in the double displacement reaction between potassium iodide this is Ki which is going to react with aqueous lead nitrate aqueous lead nitrate is Pb and O3 whole twice okay it will give you the yellow precipitate yes definitely it will give you yellow precipitate that is Pb I2 it is yellow in color okay so and lead iodide the Pb I2 that is yellow in color while performing this activity of lead nitrate is not available which of the following can be used as a lead nitrate now see here you have the option called as lead acetate you know you have to select that one which is this is aqueous this is soluble salt this is soluble salt okay you have to select the soluble salt and this is also soluble this is a kind of precipitation reaction it is a precipitate so you need to take the soluble salt if you take Pb SO4 it is again a precipitate white precipitate you can't take this lead acetate yes lead acetate will work CS3 COO- lead acetate will work ammonium nitrate ammonium nitrate will not give you Pb I2 at all you need lead in that so only option left is B only okay so B is the correct answer any doubt because you need to make Pb I2 so what will be the reaction here if I write the reaction with lead acetate Ki plus Pb CS3 whole twice this is lead acetate Pb CS3 whole twice so what it will form it will again form Pb I2 only multiplied with 2 plus it will form the acetate with potassium so you can write K CS3 COO though it is a ionic compound CS3 COO- and K plus will form is it clear so Pb I2 you need to make the yellow compound next question okay question read is which of the following guesses can be used to store is a fresh sample of an oil for a long time okay yes don't see the picture just read the option just read the question don't see the picture which of the following guesses can be used for the storage of fresh sample of an oil for a long time and read the options okay so helium and nitrogen is the correct option because you want to store something so you need a gas which is very less reactive so very less reactive nitrogen is very less reactive because of actually nitrogen is very very less reactive because of triple bond present in nitrogen and helium is very less reactive because it is a noble gas it is a noble gas so you can use this for preservation of something so I hope you got the answer and all other reactive carbon dioxide is reactive carbon dioxide or oxygen nitrogen and oxygen nitrogen is fine but oxygen is reactive carbon dioxide or helium carbon dioxide is really reactive so only option left is D okay next question okay who is M okay M Monash any doubt in this question no doubt okay next question the following reaction is used for the preparation of oxygen gas in presence of catalyst in a laboratory which of the following statement is are correct about the reaction it is a decomposition reaction and endothermic in nature it is a combination reaction it is a decomposition reaction and accompanied by release of heat it is a photochemical decomposition reaction and exothermic in nature any case please because it's happening with you is it happening with others also other than Aniket Surya also okay fine okay Pratik Shah Anirudh it's happening with maybe you are in hurry to answer and by mistake it got clicked hi it's a very less chance but still it will not happen again and again so maybe some issue is there okay so see the question is very clear why you people are made mistake in this the question is very clear that KClO3 is reacting yes and KClO3 on reaction and it is like it is solid and you are heating it so first of all it is endothermic only when you heat something it is endothermic okay and you are getting 2 KCl plus 302 gas okay so it is a kind of okay if you see it is a kind of decomposition reaction decomposition means one compound breaks into two or more so it is a decomposition so what I will write decomposition decomposition reaction and what else it is a endothermic endothermic clear should we move to next question okay next which of the following process involve chemical reaction which of the following process involve chemical reactions storing of oxygen gas under pressure in a gas cylinder liquefaction of air keeping petrol in Chinatation and open container heating copper wire in presence of air at high temperature okay most of you have answered it right but why you people are made mistake in this okay so let's discuss the two questions which are left so which of the following reactions storing the oxygen gas in a cylinder under a pressure you know chemical change we only say when there is a the when we say chemical change when there is some new new compound is forming and old compound is breaking down then we say there is a chemical reaction when you put oxygen and you condense it you will let's say liquid oxygen you get but there is no change in compound similarly liquefaction of air same thing okay keeping petrol in China dish if you put petrol it will evaporate it will evaporate but still it's a bit petroleum vapors so it is not a chemical reaction the option D is the only correcting where copper wire reacts with air copper wire when reacts with air let's say it will form a copper oxide so it is a chemical reaction okay at high temperature it will form copper oxide now there is a one question which I told you we will see it again that question I'm reading it and it was correct those who have given mercury as a answer it is correct only let's see what was the question which of the following metal will not displace hydrogen that question was right which of the following will not displace hydrogen from steam from steam dilute dilute acid dilute acid and alkali and alkali I thought they are asking for a single thing they are asking for all the three things like if any metal gives hydrogen with any of these then that will be not our answer let's talk about iron iron will give hydrogen with this with dilute acid it will give with alkali it will not give so if with any of this if it gives hydrogen that is not our answer so if I say is it my answer no it is not my answer let's talk about other zinc zinc with steam it will give hydrogen dilute acid will give even with alkali it give it will form Na2z and O2 Na2z and O2 this time I think you got this question in exam also with hydrogen gas liberated so this is also not not our answer now it's a mercury a very less reactive element as we discussed in the series where is the mercury in the series here saves green planet it is below hydrogen so mercury is our answer because it will not give hydrogen with steam also will not give with dilute acid also will not give with alkali so this is our answer let's take a last option that is calcium with steam it will give hydrogen with dilute acid it will give hydrogen with alkali it will not give hydrogen okay so this is not our answer so most least reactive atom is our answer for this question anyone has any doubt please let me know otherwise I will ask one question related to this any doubt no okay what all metals will give a hydrogen with alkali quickly tell me the answer what all matters will give hydrogen with hydrogen with alkali what all matters will release hydrogen with alkali tell me sodium will not give those who have written sodium it's wrong okay aluminum zinc and calcium and magnesium will not give alicia okay for your syllabus for your knowledge you can remember the three matters there are many but for you you can remember zinc PB aluminum these three matters will give hydrogen with alkali is also what will be the reaction I am writing in front of you zinc plus NaOH all will form some common type of formula what like ZnO2 you will get here with PB with PB and NaOH you will get the same type of formula what PBO2 with aluminum and NaOH you will get the same kind of formula alO2 but number of sodium will get differ it is Na2 ZnO2 it is Na2 PBO2 but it is NaAlO2 this is the formula along with you will get hydrogen gas along with you will get hydrogen gas here in case of aluminum you have to add water also otherwise you will not able to balance the reaction here you have to add the water so these three reactions are very very important so these three are known as amphoteric metals what we call them amphoteric metals amphoteric metals amphoteric metals are those metals which liberates hydrogen with hydrogen with alkali is also these three are in your syllabus if you want to know more metals there are there is also BE also chromium also gallium also so these are also give our amphoteric in nature but for you it is we are important I hope you got the concept behind this question so questions were alright there was one issue with the few systems like you are saying that it is taking questions by its own so we'll see this issue and we'll try that this will this won't happen from the next class any other doubt do you have any other doubt no okay so just see the final result for today's class oh good shares very good shares shares as congratulations okay so hope you learn something and you have understood the concept of amphoteric metals and our reactivity series which you can use till class 12 also you it will be helpful for you okay that's all for today okay thank you