foreign five chapter one okay form five chapter one so I'm not sure how you're doing for your form four okay but for now I'll just focus on form five first and only I will do the revision afterwards for form four okay so I'm not sure how you learn and what is your performance what you achieve for your form four final exam okay but what am I trying to tell you is that okay when you come to form five you need to change slightly the way on how you learn because many people when you come to form four they used to like they read a lot they read they read they read but when you come to when you come to the examination when you come to any test they do very badly okay so that's a very common problem for majority of the students are they understand the concept but they don't know how to apply and what even worse is that majority of the students nowadays is that okay I don't know what I don't know so this is the problem for majority of students they themselves not even know what is their problem hey they don't know what is their problem at all right uh so that is the big issue okay because the problem is what you guys don't have pd3 exam so you don't know your performance there right and then now even worse now UPSR also they demolish it they don't have the UPSR ready okay so they replaced by those school-based assessment which is kind of like quite useless actually to be frank so many students they don't know what is their own problem so how are you going to understand your own problems okay because if you come to me sir say Sir help me I said how how I can help you what you don't know I don't know I don't know what I don't know so I cannot help you one so you must first identify your own weakness first so one of the simplest ways for you to identify your own weakness is that you must do good quality question you must always do some good quality question so what do we mean by good quality question okay I want you all started from form five try to do more on the trial exam paper do the question from trial exam paper or we call it State paper and also you want to do some past year question pyq past your question these are good quality questions uh it's not advisable for you all to do the question from any reference book okay because sometimes the question for reference group might be too easy or they might be too hard all right some students can they can do all the questions from reference book but they cannot do a single question in SPF there are quite a number of students like that okay so if you really want to do the question do some good quality question like what we will do today like this okay like the question from early's the question from pahang all these State paper so the quality is there okay so this is something very important so don't keep on reading already when you come to your form five you have to start doing question when you do the question then only you know what is your weakness then only you can find some help like for example if you keep on doing the question you found that you always start at sort okay then which means your sword is not good maybe you can ask teacher you can ask me you can ask your friend who know at least you know what is your problem okay you keep on doing questions you always start at more you don't know how to do the mole calculation for example you find a way maybe you're going to watch my YouTube video you ask your friend you ask your school teacher or what so you must first understand what is your own problem first because if you if you yourself don't know your problem no people can help you out all right sorry for taking up so many time to talk about all this bullshiting but it's so important okay because many people were so lost many many students were very lost okay okay so now let me give you the overview what we will learn in the form partner so in your form four there are total eight chapters okay when you come to form five there is only five chapters okay there's only five chapters in your form five okay all right so but form five the chapters will be more longer okay phone five the chapters okay might be a little bit longer okay hold on huh all right so we have chapter one chapter one is called uh redox equilibrium no need to copy all this thing out I just give you a quick overview I will tell you what we will do in this one year okay chapter two is called carbon compound then character 2 is called carbon compound chapter 3 is called thermal chemistry chapter 4 is called polymer and chapter five okay it's called industrial chemistry okay all right so your chapter one will be the longest ever chapter you will encounter in these two years okay chapter one itself we will take approximate four months okay we will use a proximate four months just to just to learn about chapter one and chapter one is the hardest chapter in the entire form four and also the entire form five so I want you to stay focused and don't miss out any lesson if possible if you miss out the lesson please please please get the recording because if you miss out one lesson you might feel very lost already okay but don't get frightened by me you follow my step one by one step by step you will be fine so carbon compound we will spend about two months for it the more chemistry we will spend one month okay polymer about one month industrial chemistry about two weeks okay so this is the basic planning like this is the basic planning for this year okay so we will spend a very very long time on redox equilibrium so like what I say so far none of you actually uh so far none of you actually started with your housing so far none of you already started with the chapter one in your school so I assume you are just a white paper you know nothing which is good that's what I'll teach you from scratch and our tissue very very slowly okay so that you can follow me okay so let's start up so the first thing that you need to learn today are the first thing that you need to learn today is this you need to understand the word core redox okay so what is redox the word redox come from two word the first word is r e d the second word is o x read and Ox so the re means reduction so there is a chemical process called reduction the ox means oxidation so these two words very important you will keep on you will be bombed with these two words for the next four months in the next four months I'll keep talking about these two words until you want to warm it yeah reduction and oxidation so what do we mean by redox so sometimes SPM can ask you a simple question what is redox okay they can ask this what is redox and give you one mark in SPF so what is redox redox means that you have reduction and also you have oxidation these two process they occur you can use the word occur you can use the word take place you can use a simple word happen doesn't matter okay all right at the same time okay when you have oxidation processed and reduction process these two processes happen at the same time that is called redox you must have both if let's say this chemical reaction only got reduction don't have oxidation it's not a redox if this chemical process only have oxidation don't have reduction it's not a redox redox must have reduction and oxidation happen at the same time sometimes the school they do sometimes the the textbook they don't use at the same time they use a very fancy what they say reduction and oxidation occur simultaneously same thing simultaneously means at the same time okay so make sure everyone know what the definition of redox what is redox they always ask this in your paper too okay you write this you are going to get one mark so that's the first thing okay what is redox oxidation and reduction happen at the same time then some students ask Mr Martin can we write oxidation first then only reduction can we write oxidation and reduction happen at the same time I put oxidation in front can or cannot can the sequence doesn't matter it doesn't matter you write oxidation first or it doesn't matter you write the reduction first it doesn't matter most importantly you write it okay so that's the first thing we learned today okay up to this moment can you guys please respond to me in the chat box remember send a message to the public spacer are you guys okay with what is redox so far foreign very good okay very good so oxidation and reduction these two process happen at the same time it happened at the same time so that is what we call redox okay so now the next thing we need to know is this what is oxidation what is reduction these two are something new for you okay so they are total four different methods so we have four different methods in order to determine okay we have four different methods to know whether the process is oxidation or reduction okay we have four methods to determine this chemical process is oxidation or this chemical process is reduction because these two words is new for you in form four maybe you heard about neutralization you heard about combustion something like that okay but you never heard about oxidation and reduction in form four that's why it's something new for you so how I how am I going to know this chemical process is oxidation or this chemical process is reduction how to know okay let me teach you a very simple way and then we will do some past year question directly so you know how to apply it so let's look at it so there is a very important table for you okay to see that so this is the method okay so we have four method okay the first method is you can look at the oxygen we call oxygen method second method is called oxidation number method okay we will learn what is oxidation number eight or no worry and we can look at hydrogen method then we can look at the last one called electron method no worry when you first started of course you'll feel confused one which is completely normal yeah there are four method we can use okay so I teach you a very simple way to memorize first then I'll explain to you one by one okay I'll teach you a simple way to memorize Versa okay so how to memorize it so I teach you a simple way to cheat up so look at the first letter to look at the first letter here you see here right this first letter is O this first letter is O if the first letter is the same put a plus o and O the first letter is the same Plus o and H the first letter is different put a minus o and E the first letter is different put minus so here everything the valid plus plus minor minus the valid minus minus plus plus okay what do I mean if this chemical process plus means plus means gain the plus means gain or increase okay the minus here means lose or decrease so if this chemical process gain oxygen it is oxidation for example let's say this is me I'm a human initially I got four oxygen in my hand okay I got four oxygen in my hand so when I undergo a chemical process now in my hand God 7 oxygen already okay so now my oxygen increase so when I increase the oxygen I undergo oxidation process same thing like the ballet if I decrease the oxygen I undergo reduction so let's say initially I got four oxygen on my hand so now for oxygen now or inserted become only one oxygen so I lose oxygen right from four oxygen only left one I lose oxygen so that is reduction that's it so this is oxygen method we will learn more later next one oxidation number oxidation number we will learn later also on no worry okay so this one a little bit tricky we learned later okay next one same thing hydrogen so if you lose minus means loose if I lose hydrogen I undergo oxidation if I gain sorry if I gain hydrogen I undergo reduction so same thing let's say initially I have a substance okay on the left hand side let's say I got wh four I got four hydrogen on the left hand side go to right hand side becomes w h two from four hydrogen become two hydrogen so what happened I lose oxidation yeah I loses hydrogen already so when I lose hydrogen so look at hydrogen loose means minus so loose hydrogen means oxidation process so that's it okay so by looking at these four different perspective then you know already whether the reaction is oxidation or reduction so same thing if I gain electron if this chemical reaction gain electron if I receive electron from other people undergo reduction if I lose electron I donate electron to other people I undergo oxidation okay so this table is the most important thing in your entire chapter one if you don't know this table you cannot move on with chapter one anymore so of course when you first started you'll feel confused which is okay which is normal okay so how are you going to familiarize yourself easier and faster take a piece of paper this table copy for a few times every day copy this table for one time do it continuously maybe one week you copy three times do it continuously for one or two weeks then you will be able to remember you won't forget already okay this is very very important okay you must know this table okay now why this table so important and how the question can be tested in the real examination how actually they can ask us the question okay right so let me show you uh how the question can be asked so let me show you the question here okay so this question is all coming from good quality question all the questions I'm showing you today they are coming from trial exam paper okay they are coming from trial exam paper so let me show you the first one this is the first question coming from and also this is coming from Malacca okay so what they want so they say first one question which of the following occur in reduction reaction which of the following occurred in the reduction reaction so reduction so how I do it so remember let's do a table oxidation reduction so there are four method first method oxygen method second method oxidation number method third method is hydrogen method fourth method is electron okay four method so how to remember look at the first letter O and O o plus o and o plus o and H different letter minus o and E different letter minus the valid minus minus plus plus so what they want they want reduction so focus on reduction here so reduction gain oxygen yes or no oxygen reduction is What minus minus means lose so it's wrong so let's look at B gain electron so reduction electron electron is plus plus means gain so the answer is B so can you guys please type in the chat box and let me know are you okay with this concept so far so this question is very straightforward if you understand the table if you can memorize this table is super super straightforward same thing if you don't know this table at all you cannot do if you don't know this table at all you cannot do that's why this table is so important yeah this table it is so important okay so now let's move on let's try I'll do a few more that I let you try okay I do a few more with you all then okay I'll let you try okay come yeah this is Malacca people same thing which of the following statement does not correctly describe the reduction so does not mean do you want something wrong something wrong lose oxygen yes or no oxygen lose oxygen it is reduction yes but we're looking for something wrong gain hydrogen yes or no hydrogen gain hydrogen reduction yes but we want something wrong lose electron so let's look at electron electron Lucid should be oxidation so wrong because we are looking for something that's not correct so the answer is C okay so actually it is very very straightforward you know this table uh you are good to go okay you know this table you are good to go okay so let me copy this table first up okay so now let's try another one okay here okay this one so this is a question from Johor this is a question from Johor probably you want to try this try these two questions type in the answer in the chat boxer let's say for the first question the answer simply say let's say the first question the answer is a second speed simply say you type a comma B in the chat box okay let's say the first answer is C second with donkey you type in the chat box okay let's say you don't know how to do the first question you type cross second one you know how to do you can type B if both questions don't know you type both process okay I want at least you reply me I want you all to reply me come on that's right let's try this you are allowed to refer to this table by today yeah okay for today this table I will give you but in another one or two more lesson you need to memorize this table on your own come on let's try it foreign okay very good okay very good response so far fantastic guys a and Bia right fantastic so just refer to Tableau again hydrogen hydrogen gain reduction that's what they want okay so the second one it's reduction also so reduction so let's focus on this roller so what they do is that okay gain hydrogen okay the reduction hydrogen plus plus means gain so it is very very straightforward okay if you understand this stable if you understand this table everything will be easy for you okay everything will be easy for you okay so that's the first thing that we learned today okay come on let's move on and learn something new so this is first part for today okay so the second part for today yeah the second parts that we need to learn today is this okay let me move you back okay so the second thing you need to know is this okay all right so now today I'll teach you probably two methods oxygen hydrogen if we got time then I teach you oxidation number method as well so we see this four method this one is easy this one is easy this one is hard and this one is hard okay so in chemistry you see this is the one easy easy and harder so SPM normally will ask you the hot one the easy one they sell them as a right but we have to start from the easy one so today I'll teach you these two method first if you got time we learned this method as well okay one by one we learn slowly no rush we are not rushing huh okay first lesson is always the most important one I do super slow so that you all can follow me okay let's start with the first one come on the first method is called oxygen method okay so listen carefully so if you guys understand oxygen method then the then the remaining part will be easy okay because many many methods are very similar one there are many methods actually they are very very similar ones so if you understand the first method the other method would be quite easy for you okay so let's start with it so for oxygen method so what we need to do okay how to do oxygen method and what is it okay so let me show you now okay so if you want to do the oxygen method okay first of all you need to understand a very important thing we call it as Apple to Apple comparison okay we need to do a very important thing called Apple to Apple comparison okay so what do we mean by Apple to Apple comparison okay so let me show you something first let me show you something first okay all right here okay so oxygen method we only focus on oxygen so we only focus on whether we gain or lose oxygen okay we don't look at other things okay so what is the strategy that you need to use okay this strategy can use for any other method we call it Apple to Apple comparison okay what do we mean by Apple to Apple comparison okay listen carefully yeah so when you do Apple to Apple comparison you must always always choose the right person to compare okay you must always compare the right Apple you cannot take apple compared with durian cannot it cannotic Apple compared to rambutan so how to choose the right Apple okay how to choose the right pair to compare okay so listen carefully yeah so there are three things you need to do here first thing you always need to choose one Feller from the left and then you always choose one from the right so must be one left and one right you cannot choose two from the left you cannot choose two from the right must be one from the left one from the right okay so you must always choose something that is related to something that is related no worry later I'll use two to three examples to show you so you will have a better idea okay so then you have to be careful with the sequence okay so you have to be very very careful with the sequence that we are doing when you're doing the comparison is always left go to the right you cannot the valley you cannot go the other way around you you cannot compare right to the left okay what do I mean okay the best way to learn is by example I will use three examples to show you so that you have a better idea so if after three example is still very blur please ask me okay so the first example let me teach you this so the first example we have something like this this is a magnesium and then this is a copper oxide this is magnesium oxide and this is a copper okay all right so how are we going to use oxygen method to do this questionnaire so first of all look at the step first go to choose the right one filler from the left and one color from the right choose something that's related okay you see up let's say I choose one apple from the left the first Apple I choose is magnesium so can I choose copper oxide already cannot you must use one apple from the left and one apple from the right so now the right hand side got two apples right the two right hand side got two apples which Apple we should choose they must be related to the left can we choose copper cannot magnesium and copper has nothing related no common thing nothing related at all magnesium copper totally different you will choose magnesium oxide why they got relationship this is Magnesium this is magnesium oxide both of them got mg so at least you can see they are related okay so these are the Apple that you want to compare let me know in the chat box are you okay so far okay always always choose the right pairing right pairing for comparison so can we do a comparison now yes let's look at it let's look at the red red color error would you compare always left to the right not right to the left so let's say now I compare the left to the right so left to the right what you can see on the left hand side magnesium is alone on the right hand side magnesium sticking with oxygen here magnesium but other oxygen here the Magnesium are the oxygen so from no oxygen become got oxygen what happened gain oxygen okay so now you can see already magnesium gain oxygen so magnesium increased oxygen so as what we learned today the four different methods so when I gain oxygen what process that is happening sedation okay so magnesium undergo oxidation so magnesium undergo oxidation if you don't want to say magnesium undergo oxidation you can put a past tense like this you can you can also write okay magnesium is oxidized make it a past tense magnesium is oxidized okay magnesium suda undergo oxidation same meaning what so you can write either way you can write the first one or you can write the second one up to you okay so magnesium undergo oxidation already okay now let's choose the second Apple to do comparison so now the second apple is copper oxide so now compared to another Apple this one copper oxide and copper they are related right why this further got CU this further got CEO so they have they are related so from here to here remember left compared to the right not the right compared to the lever the that the sequence is important because the sequence is very important left to the right so left hand side Apple compared to the right hand side Apple so what you can see on the left hand side the Copper got oxy decision on the right hand side copper don't have oxygen so what happened this further copper oxide lose oxygen so when you lose oxygen what happens so that's what we learned oxygen if you lose it so it is reduction process so it's reduction process so you can say that these follow copper oxide loose oxygen copper oxide undergo reduction if you don't want to say the word undergo reduction you sorry I write wrongly sorry guys my back my back okay you can say undergo reduction if you don't want to say undergo reduction you also can use a past tense copper oxide is reduced suda undergo reduction also can so now look at it so in this chemical reaction you have oxidation in this chemical reaction you also got reduction so when oxidation and reduction these two process happen at the same time this whole chemical reaction is a redox okay so this is redox reaction so guys up to this point is it okay so it's not very hard now like what I say you just need to make sure you choose the right Apple if you choose the right Apple you do the right comparison uh everything it's easy okay everything is easy okay if you're able to do this okay right not very hard ones but it's all begin with choosing the right Apple okay it's all begin with choosing the right Apple first okay so we're done come on so let's do a few more income let's do another few more okay example number two okay later I would like you all to try okay later I will let you all to try some questions later okay but now just follow my footsteps let me guide you first okay let me get you step by step okay example number two okay so let's say I go for another example it looked like this okay all right here we have okay yeah uh let me read like this again [Music] Korea pbo2 plus C become p b o plus c o okay same thing we are now still focused in a oxygen method other method don't bother don't bother yet okay so let's choose the first Apple so the first Apple I choose is what this one one apple from the left so we choose one apple from a left you need to choose another one apple on the right so among these two apple on the right you will choose the first or the second one to compare guys you choose the first or second one to compare with that with the Apple okay very good you choose the first one right because at least you see something related right or not okay this will look like PB this product or PB you can see they got relationship they got relationship so that's it so compare left to the right left hand side the PB got two oxygen right hand side the PV got one oxygen Two Become One oxygen becomes lesser so lose oxygen pbo2 loses oxygen so that's what we learned today when we lose oxygen the process is reduction process the process it is reduction process so reduction pbo2 undergo reduction or you can say is reduced okay let's say I use the past tense settle so now let's choose the next apple to do the comparison so the next apple that we want to do the comparison is here carbon is another Apple compared with Co so these two are related right here got C here got Sila so on the left hand side the carbon come alone on the right hand side the carbon sticking with o so no o got O So increase in oxygen so the carbon gain oxygen so when you gain oxygen you undergo oxidation you can say undergo oxidation or you can say is oxidized so this chemical process is it a redox guys is this a redox process yes or no is this chemical process a redox yes or no yes right because Ada oxidation other reduction when you have oxidation you have reduction these two process happen at the same time yes it is redox yes okay so settle so it is redox so done okay so don't think very hard right so as long as you understand the logic okay as long as you understand the logic you are good to go okay you are good to go up it's not very hard actually okay right so now let's look at here let's look at one uh positive question so no positive State paper let's do one state paper this question is from 2022 per Lisa police trial exam paper so online per tuba and police so they give you this chemical equation like they give you this chemical equation they ask what is the reaction happen on copper oxide so copper oxide is this further so when you want to know what happened you must use the right Apple for the copper oxide compared with the Apple copper left hand side this Copper got all right hand side this copper don't have all so what happened here lose oxygen so loose oxygen is what process anyone can type in the chat box to let me know loose oxygen is what process okay fantastic loose oxygen is reduction so the best answer is a quite easy isn't it okay that's exactly how the question can be tested in the real exam is that easy only okay choose the right Apple do the right comparison you are good to go as simple as that okay that's it okay now let us increase the difficulty okay let us increase the difficulty a little bit more okay when you come to chemistry another very important words is this okay in chemistry you will see this one these important words and this one might be a bit confusing huh so I'm gonna go very very slow to to make sure that you really can get the idea I'm gonna go very slow to make sure you can get the idea okay so listen carefully so this is the side notes okay so in chemistry okay so we have some super agent we have some special agent okay uh so you see when you watch some super Say superhero like you watch some movie okay you can have zero zero seven those like secretive agent isn't it so chemistry also got some secretive agent okay so you have two agents listen carefully yeah the first agent called oxidizing agent the second agent is called reducing agent and what do we mean by oxidizing agent and reducing agent oxidizing agent means what you are the agent to oxidizing oxidizing means you let other people who undergo oxidation so you go to let other people or other substance to undergo oxidation you oxidizing oxidation means you let other people to oxidation okay undergo oxidation this will be a bit confused no worry I go very very slow reducing agent I am the agent what I do reducing let other people to undergo reduction so I go to let other substance undergo reduction okay what do I mean okay it's here so everyone take uh take a look on this today this is substance a or this is mean this is me you mix me with oxidizing agent hey you mix me with a fella this Furler is called oxy daising agent okay some people say it's Mr Martin why sometimes in the books I saw the red oxidizing agent some they write oxidizing agent the S and the Z it doesn't matter this has nothing to do with chemistry this has something to do with English whether you are learning the UK English or you're doing the US American English it's okay what both also acceptable it's just English only no matter you write s or Zack both are okay yeah so if I I am I am a substance called a I mix with oxidizing agents so what happened oxidizing Asian what they will do they will let me undergo oxidation so later on the a will undergo oxidation uh so oxidizing agent let other people undergo oxidation process same thing today if this is a reducing agent if I mix with reducing agent reducing agent will make me undergo reduction process okay so when I say Asia means what you want to help other people Asia means you want to help other people oxidizing agent you help other people undergo oxidation reducing agent you help other people undergo reduction process okay so this is something very important okay now the next thing how on Earth we can know the substance can is oxidizing or reducing HR this will be very very very tricky area this will be very very tricky already okay so I put five star here so that you know how important it is okay not one star not two star not three star five star so this concept very important so what is it so listen carefully okay when you come to chemistry you need to understand this okay you need to understand that all the chemical substance they will always act or they will always behave as the special agent for the opposite okay for the opposite process okay that themselves undergo okay and this will be very tricky this one will be very very trickier so you will be the agent for the opposite process that you yourself undergo okay all right so what do I mean okay what do I mean okay let's say yeah I am a substant air so let's say I am substance a me myself undergo oxidation process I undergo oxidation process okay I undergo oxidation process so I will be agent also when I undergo oxidation I am qualified to be agent so the agent will be opposite of this so if I undergo oxidation I will be the opposite agent so I will be reducing agent because the opposite of oxidation is reduction so I have I am reducing agent so you will always be the agent for the opposite process that you yourself undergo let's say I have another substance called substance B so I have substance B substance B this substance undergo reduction so if I undergo reduction process myself so what who am I so if I undergo reduction process I'll be opposite so I will be the opposite agent of this reduction opposite is oxidizing so I am oxidizing agent okay so when you know what process that you yourself undergo you will know exactly what agent you are so I undergo reduction I am oxidizing agent I undergo oxidation I am reducing agent so this part might be a bit confused let me know are you guys okay if you are okay can you type okay if you don't understand put a cross in the chat box let me know it's okay to say not okay right so you have to be very very careful with this okay right good so I can see probably there are so far got one okay got one student's not really understand okay never mind is there any other don't understand is there any other student understand okay so let me go one by one all right Okay so okay so I hope I pronounce your name correctly yeah okay so so let me let me go through this this one okay so I want you to follow me yeah I want you to follow me okay first of all okay do you understand what is oxidation reduction the basic thing first do you understand basic oxidation reduction first okay so now allow me to ask you a simple question let's say okay now a plus b o become a O and B okay so I want I want you to answer me Audrey fashion so now I want to do Apple to Apple comparison so which one I should compare you let me know the number who and who I should compare when I do Apple to Apple comparison let me know which pair I should compare if I choose a here I should compare with who okay three out one and three two and four very good okay I chose one and three two and four okay let's say I one and three I compare Apple to Apple okay so can you let me know a to a o what is the process happen on a what process a undergo what process a undergo very good oxidation that's it 8y for the report for the other students you can see here a become a o what happened in oxygen so when a gained oxygen according to the table that we learned today gain oxygen means oxidation so when you get when you undergo oxidation what is the agent you are so remember you will always be the agent or the opposite process that you undergo if you undergo oxidation process what agent you are that's it reducing agent so do you get some idea now okay let's try another one hey guys come on b o to compare with B Apple to Apple comparison b o to B got o don't have o what happened loses oxygen so loose oxygen what happened b o undergo reduction isn't it Loose oxygen is reduction so guys can you cut in the chat box if Bo undergo reduction what agent it is what agent it is fantastic very good Haida all right very good Duncan all right Joey Eliza all right very good oxidizing you get it okay as simple as that so don't mess up okay I'm talking about two things first of all I tell you all what do we mean by agent Asia means what I can help other people who undergo a specific process if I am oxidizing agent I help other people I may go oxidation if I undergo if if I am reducing agent I help other people undergo reduction process that's it so that's what the agent do then how on Earth I know this color this substance is what kind of agent so I must know what process they undergo because whatever process you undergo you will be the opposite agent if you undergo oxidation you will be opposite opposite of oxidation reduction reducing agent if you undergo reduction you will be opposite agent opposite of opposite of reduction is oxidation oxidizing agent that's it you will always be the opposite agent for whatever process that you have undergone that's it okay so simple as that as simple as that so now we can come back here and we can complete the remaining thing already come example number one just now okay so like come on maybe we'll open our new one we open up a new one and maybe I give you two minutes for you to try together okay for you to try together with me okay so I do example number three with you all okay I do example number three with you all okay all right example number three app okay so let's say example number three we have this Zack and Zing react with oxygen O2 to become two zinc oxide okay this question is not hard but it's a bit tricky for some people it's a bit tricky for some people okay listen listen carefully okay listen listen carefully yeah how are we going to to do this question how are we going to do this question okay first of all same thing choose the apple and apple comparison first or we choose one apple from a left one apple on the right so first Apple on the left let me choose this color so apple on the right no choice there's only one here of course I choose this one so when you compare the left hand side the zinc right hand side is income with all quite easy no o God oh so here to here so what happened is zing actually gained oxygen so again oxygen means reduction so when zinc undergo reduction it will automatically become the opposite agent so the zinc itself become reducing agent now remember when I undergo oxidation I will be reducing agent it always go opposite it always goes the value so settle now let's look at the uh another one another Apple so now I choose another apple on the left so which apple I want to compare the right same thing so I still compare with this further so sir I thought just now we compared already I didn't say you cannot repeat right I only say You must compare the left and the right choose one apple on the left and one apple on the right I didn't say you cannot compare back to the same Apple isn't it okay you can compare back to this apple although this apple just now compared with here already you can reuse the apple and compare with this color it's okay so let's do it left hand side O2 two oxygen right hand side one oh now be careful what many students they will start to say Sir you've got two all right here got two o my red oxygen doesn't change okay listen carefully when you do Apple to Apple comparison please please please don't border the number in front all the number in front here only used to balance the equation all the number in front here only used to balance the equation when you do the Apple to Apple comparison do not border the number here don't look at the number in front so only look at O2 and z and O this number two don't look at it so O2 for how many oh two Z and O go how many oh one two o become one o so what happened lose oxygen so the ox O2 loses oxygen so loose oxygen means reduction when you undergo reduction you are opposite or c dicing agent okay so guys now based on this question up to now is it okay so far so good is it okay if not okay stay no okay so far so good okay so I want you all to be honest with me not okay just saying not okay I don't feel bad wow 40 people say okay I am the only one who say no okay I feel bad no don't think like that please don't think like that okay I'll try my best to help you but you just need to be honest with me can I right so you see guys you make perfect sense when you see yeah you see you make perfect sense one why I say or O2 is oxidizing agent oxidizing agent means what you help other people to undergo oxidation make sense my O2 give one o to The Zing right o two e one oxygen to the zinc so that it becomes like and also when I give oxy to the zinc I let the zinc to gain oxygen when I let the zinc to gain oxygen I help The Zing who undergo oxidation isn't it that's what I do okay same thing the zinc will take one oxygen from O2 so when zinc take one oxygen or O2 zinc will let the oxygen to lose oh Zing will let the O2 to lose or when I let other people to lose oxygen okay so what is it I let other people to lose oxygen I let the oxygen to undergo reduction when I help this oxygen to lose the oxygen so I am reducing agent it makes sense right zinc is reducing agent why I let the O2 undergo reduction how I let the O2 undergo reduction I take away o from the O2 when I let the oxygen to lose the ox when I let the O2 to lose oxygen the O2 undergo reduction that's it so that's what happened Okay so when I am agent I help other okay so that's why I don't confuse first of all you must know what the agent do oxidizing agent what you do you help other people undergo oxidation reducing agent what you do you help other people undergo reduction how to know who is oxidizing agent who is reducing agent you just need know what process it happens okay if you undergo oxidation you become the opposite agent reducing agent if you undergo reduction process you become opposite agent oxidizing agent I keep on repeat repeat and repeat because this is so important this is very very important okay that's it okay so that's how it works okay now the last example this is for you maybe you can try to do okay I would like you all to try to do this question you can try to do this question you do like what I did okay you must know who gain or lose oxygen what process it undergo and what agent you are so tell me trading okay follow exactly what I do okay draw the proper Arrow choose the right Apple do the right comparison tell me who gain or lose oxygen tell me who undergo oxidation reduction and tell me who is the oxidizing or reducing agent okay so this one is a self-test for you all okay so after this self-test then we will move on to the hydrogen method because I believe if you understand oxygen method you shouldn't have a big issue when you move on to hydrogen method because they are very very similar come on so this is a self-dest where you are this is a carbon this is a carbon dioxide and this is a carbon monoxide so guys right you can try so you just need to tell you just need to follow exactly what I do something like this okay you try first come on okay so once once you are done you type done for me okay if you finish already type done so I want you to do like exactly what I do choose the right Apple do the right arrow tell me what process it happens tell me what agent it is okay come on take your timer all right some might do it very quickly some might take a longer time it's okay don't compare with others okay follow your own pace follow your own pace yeah foreign foreign foreign so you must choose one apple on the right right hand side you don't even have a choice must be this so left to right so you want to go top you want to go bottom up to you it's okay one so let's say go top this carbon got no all this carbon got one oh remember when you compare this number two don't bother don't bother number two and try only compare the formula the number in front only for balancing C becomes Co you gain one additional oxygen so you gain oxygen so carbon gain oxygen so carbon undergo oxidation so carbon it's reducing agent and of story so another Apple to Apple comparison choose another apple on the left CO2 so you must choose one apple on the right so this apple although just now you use already now you can use like the same Apple okay nevermind CO2 becomes cor remember the two Dome border okay if you put the two you confuse rate you've got two oh he got two or cannot num the number in front don't border okay don't bother CO2 to co so what happened CO2 or 2o Co got one o so one oxygen went missing so CO2 lose oxygen so loose oxygen undergo reduction process when you undergo reduction you become the opposite agent oxidizing agent and of story okay so with that being said we are all done with the oxygen method okay so the first method is all done let me know in the chat box guys so far are you guys okay with oxygen method so far I want to make sure everyone okay first thing only and move on okay guys very good okay very good so you guys can follow right okay uh so I may want to go so slow and my mom want to go this low and I remember my purpose they go very slow to make sure you really can understand okay I go fast no people can understand no point okay no point I'd rather go super slow but you can understand okay now let's go on with hydrogen method hydrogen method is very very rare in spma not popular okay not popular but if you understand the oxygen method you shouldn't have a big issue with the hydrogen method okay uh hydrogen method you follow exactly what oxygen method do with it okay you just need to focus now on hydrogen okay hydrogen method is the least popular method among four so we have formatted the least popular one is hydrogen method okay so same thing now we just need to focus on whether you gain hydrogen or whether you lose hydrogen okay so if you understand the so-called oxygen method you shouldn't have a big issue at all when it comes to the hydrogen method okay let me show it to you okay let me show it to you now huh right so how to do the hydrogen method how are we going to do the hydrogen method okay so let's see yeah if we will use uh two examples okay I'll use two examples also to do the demonstration okay I'll do the demonstration here okay so let's say the first example I'll show you one example and then I show you one keyboard question okay for example number one let's say yeah H2S hydrogen sulfide react with chlorine so that you become hydrogen chloride and you become sulfur so same thing now we just want to focus on hydrogen okay we just want to focus on hydrogen just now we focus on oxygen now we focus on hydrogen as simple as that okay right so same thing first of all choose the Apple first always choose one apple on the left always always begin with one apple on the left so which Apple you want to compare with the right hand side here sulfur why don't you compare this one okay why don't you compare this one you see this further got two H this for logo one H looks good but here the sulfur why all the sulfur becomes no there's no way sulfur become chlorine or inserted becomes something else doesn't make sense so if H2S and S at least make sense but why got sulfur got sulfur then you can see this sound first sticking with two hydrogen this sulfur got no hydrogen so from here obvious not so you can see that from left to the right hand side the H2S lose hydrogen okay now look at hydrogen method that we learned early on today so if you look at hydrogen method when you lose the hydrogen it's oxidation so the ballet hydrogen matter exactly the body of oxygen when you gain oxygen oxidation now hydrogen turbulate hey when you gain hydrogen reduction so hydrogen and oxygen exactly turbolic exactly the Valley air all right opposite so when hydrogens sound quite lose oxygen so you undergo oxidation all right uh if you're not sure just refer to the table just refer to the table so when you undergo oxidation same thing you'll be the opposite agent so you will be reducing agent okay all right so now another Apple to Apple comparison so choose another Apple chlorine another apple is HCl doesn't make sense makes sense ma here the CL got nothing here the CL got hydrogen so you can see already on the left hand side the chlorine don't have hydrogen on the right hand side the chlorine got hydrogen so you can see look the chlorine here scale hydrogen so when you gain hydrogen chlorine undergo reduction isn't it okay remember refer back to the table gain hydrogen means reduction so when you undergo reduction which agent you are opposite of so when you undergo reduction you are the opposite agent so you are oxidizing agent and of story is this a redox reaction yes because I have reduction I have oxidation re-docs okay so when oxidation and reduction process happens at the same time then it is a redox process okay so now let me show you another example so this is a k but this is a k bar or we call it a hot this is hot means higher order thinking skill okay so higher order thinking critical thinking questioner okay so how am I going to make this question become a k but question okay so Kmart question they can do something called two in one so two in one means that they can combine oxygen method they can combine the oxygen method as well as they can combine hydrogen method so this is special because just now if you remember all the example we use is purely oxygen method or purely hydrogen method but now they can make it become a Kmart whereby we will use both two method all come in together no worry no Panic just do as usual just do it as usual okay right let's say yeah we have this ammonia react with copper oxide become nitrogen gas water and copper okay so no worry okay just follow my my lead okay I'll lead you I'll teach you what to do so first and foremost before you do apple and apple comparison don't be so excited yet always always make sure when you have a chemical reaction the first ever thing you need to do is what balance it always remember whenever you get a chemical reaction just balance it before balance the equation don't ever do your Apple and apple comparison okay so I balance it quickly yeah let me let me balance it two three three x-ray two three three yeah so you can balance yourself so now let's choose the Apple to compact let's choose the apple and apple to compact so let's say I choose one apple on the left okay so we choose one level on the left so tell me guys this apple on the left I should compare with who one two or three if I choose ammonia on the left I should compare with who one two or three okay very good okay very good I should compare with number one okay I should compare with number one huh makes sense these nitrogen sticking with hydrogen these nitrogen not sticking with hydrogen so obviously you know which method you need to use the hydrogen method isn't it so ammonia is actually losing hydrogen so loose hydrogen what process is happening oxidation right loose hydrogen is oxidation processed when oxidation process takes place you will be the opposite agent you are reducing agent okay you are reducing agent and of story now let's choose another Apple to do comparison green apple copper oxide now I want to compare with who one or two copper oxide who I compare one or two okay let me see the chat box first okay very good okay Zoe Eliza Cynthia okay singing okay very good compare with two so that's what I say you must know which Apple you should compare that's the most and basic thing okay you choose the right Apple you won't get wrong ah right unless you're telescope so copper so come to here okay remember left to right not right to left okay so on the left the copper sticking with o on the right hand side the Copper got nothing no oh so lose oxygen so copper oxide lose oxygen so lose oxygen what process we learned early on oxygen method loose oxygen is reduction isn't it okay reduction so when you undergo reduction you are opposite oxidizing a churn okay that's it all right simple as that so you see this one I not even need to purposely do it you see this is hydrogen method this is oxygen method I not even the purposely think about it I just choose the right Apple I see a this one the oxygen is a bit of oxygen method line in this one the hydrogen disappear hydrogen method I not even need to purposely memorized I follow the flow naturally I follow the flow naturally and I get answered already as simple as that then some people say Mr Martin this further we haven't used what this copper oxide nothing more while just now I only tell you you need to choose one apple on the left and compare with the apple on the right I didn't say you must use all the apple right uh some of the Apple you don't want to use it it's okay not to say You must use all the apple one it's okay all right so with that being said we are all done with high drawn method okay we are done with hydrogen method already okay so the paste is quite good so far so we have managed to complete two methods okay guys let me know in the chat box how's everything how's everything okay not very Halal not very Halal right so not very hard okay it's actually do a bow okay it's very very doable okay so if you really understand you follow the logic it's not that harder okay all right so let's see okay any question I can do with you okay any question here all right so okay here here okay this one oxidation number later okay okay all right so now I'll teach you the third method which is the most tricky method okay which is a super super technical method okay we will try to finish it in the next 30 minutes I go very very slow if I cannot finish today never mind okay I'll finish it next week okay but this is very important that's why I'm gonna go very slow now okay so now let's do it okay so now we have completed these two easy method so now we are moving toward to these two heart method so I won't touch electron method for sure today right I'll only touch oxidation number method okay so this is very very technical okay I want to hopefully okay I can I can teach in a way that most of you can understand if let's say after this you still don't understand you can watch back the playback of the video if you still don't understand feel free to ask me anytime yeah don't be shy ask me please ask me yeah if you're not sure so now let's look at the heart method Radia so the hard method we need to learn is called or c itation method oxidation number method okay so oxidation number method okay this is a very popular method in SPM super duper popular super duper popular in SPM okay so when you come to oxidation number method okay so I will teach you two things that today I want to teach you a few things first up okay first of all I want to teach you this hey there are total four rules to determine the oxidation number okay so you need to know what is oxidation number and how to get it how are we going to find the oxidation number for a substance okay hopefully in about 20 minutes time whenever I give you a substance you will be able to tell me the oxidation number for that particular substance I repeat that hopefully in 20 minutes time okay whenever I give you the oxy I give you a substance you will be able to tell me okay what is the oxidation number of that particular substance okay so let's start okay so there are total four rules okay I will go through one by one and we're gonna give you a lot of examples so that you can apply you can apply whatever things that I want to tell you now okay so rule number one okay so rule number one okay just a moment just one more minute okay okay all right so why oxidation number method is so popular okay why oxidation number method is so popular because oxygen number method can use for all the cases every single case can use okay Like Oxygen method can only use if the question got oxygen hydrogen method can only use if the question go hydrogen let's say you see guys let's say I give you something it is magnesium plus okay uh uh this magnesium plus hydrochloric acid become magnesium chloride and hydrogen or maybe I go for another one okay let's say this one sodium plus chlorine becomes sodium chloride do you think we can use oxygen method in this question yes or no can we use oxygen method in this question no right okay can we use hydrogen method in this question yes or no can we use hydrogen method in this question no right you see that so oxygen and hydrogen matter they're quite easy but they has they have a weakness okay many many K's cannot use if the question don't have oxygen if the question don't have oxygen then cannot use the ready okay so oxidation number method is so important and so popular because you can use in all situation okay because you can use it in all situation okay you can use in many condition or many situations ah no matter the question got oxygen or not no matter the question for hydrogen or not oxygen oxidation method can be used you can use oxidation of a matter okay so let's look at the Rua rule number one okay rule number one you need to know that the oxidation number of okay the oxidation number for element okay oxidation number for element okay it's always always [Music] zero so oxidation number for elements is always always zero okay allow me to ask a simple question here allow me to ask a simple question here guys any one of you here don't know what is element anyone of you don't know what this element if you don't know what is element can you type me if you don't know what is element can you type me for me m e okay so let me let me teach her okay element is something you learn in form four chapter two okay form four chapter two our element so what is element element is referred to anything that is made of one species so anything that is only made of one species okay what do you mean is that one species okay for example let me give you a example okay Zing is an element because only one species right only one type of substance here zinc aluminum is only one type of substance aluminum only nothing else so it's one type of substance one species only is element o two oxygen don't get cheated by two although you have two further but both of them are old they are same species right both of them are old you only have one type one type of substance so they are element let's say sulfur S8 don't get cheated by number eight although you have eight Fuller but all the eight substance all the eight substances they are sulfur all of them are same species so they are element so as long as you have element all their oxidation number it's zero okay so when you have element the oxidation number is zero so you almost know what is element anything that is made of one species only so that is element so guys carbon dioxide is it element yes or no carbon oxide is it an element yes or no Noah because you've got carbon you've got oxygen you have two elements you have two species so you are not element all right so element must have only one species okay so that's it so if you have element the oxidation number will automatic become zero okay rule number two okay rule number two okay oxidation number for ion it's always stay as DIA okay charges okay oxidation number of ion is always same as their charge okay so what is Ion anything got charged so if you know anything or charge the oxidation number is exactly same as their charge example you have n a plus is it ion yes because we've got charged so n a plus what charge is Ion so for iron the oxidation number is same as the charge so it's positive one okay so let's say aluminum al3 plus what is the oxidation number copy back the charge plus three so guys here you have to be very careful here you have to be very careful when you go for charge in chemistry when you write charger you write the number then only the sign isn't it like oxygen all two minus you don't write o minus two you write the number first then only the charge so charge you always write number then only the sign but when you come to oxidation number just like normal number you must write The Sign first then only the number okay so please be careful what if I ask you what is the charge for aluminum three plus what is oxidation number for aluminum plus three so there are some small difference okay so let's say O2 minus what is the what is the charge 2 minus what is the oxidation number minus 2. CL minus what is the oxidation number minus one okay so make sure you know the nitrogen and three minus what is the charge 3 minus what is the oxidation number minus three so guys can you please let me know in the chat box which is very important do you guys know the difference between charge and oxidation number do you guys okay with it so does the arrangement like the arrangements slightly different are charge three plus oxidation number last three okay and this is very important because when you do mathematics when you do mathematics normally you don't show the sign right you normally you don't show positive side isn't it but when you come to oxidation number you must show the sign no matter is positive or negative okay so this is a tips okay you must show the sign for oxidation number no matter it is positive or negative because in mathematics normally we don't show the positive sign but not for oxidation number oxidation number you must always show the sign okay this is rule number two so now let's look at rule number three okay so rule number three okay so now we go for oxygen oxidation number of oxygen it's always always negative two okay oxidation number for oxygen it's always always negative two okay let me change a bit huh all right so the red color is important okay so oxidation number for oxygen is always negative two except tools a few special cases which I'll show later okay let's say water water got oxygen so the oxygen here is negative two magnesium oxide your oxygen the oxygen here is negative two okay so let's say we go for something that looks weird carbon dioxide carbon dioxide got oxygen so the oxygen here is -2 okay uh so let's say aluminum oxide aluminate oxide got oxygen you don't bother how many oxygen it has you don't bother you have one oxygen you have two oxygen or your three oxygen don't bother all the oxygen the oxidation number is minus two that's it the quantity of oxygen are important okay no matter you're one two three or eleven oxygen doesn't matter all the oxygen the oxidation number is negative two that's it so you have two Special K slot okay when you have O2 when you have O2 what is the oxidation number O2 only have one species right so it's element so that's what we learned today element what is the oxidation number guys element what is the oxidation number we learned just now in rule number one very good zero okay O2 although you have o but it's not negative two because O2 only have one species so it's element element is zero is it just now all the O here comes with something else the O combined with h the O combined with mg the O combined with C the O commodity aluminum so all these they are not element okay uh so when you are not element the oxygen is always negative two but if the oxygen only comes alone if the oxygen only have one species you are element then you are zero okay so you have to be very very careful okay that's it another one which is super well are they sell them as in exam like for the past 25 years they only ask three times for the past 25 years they only ask three times so not very important okay which is H2O2 so H2O2 the name is called hydrogen peroxide if you cannot remember the name doesn't matter doesn't matter so H2O2 just like a water water got one over this is water with one more oh two oh that's it okay hydrogen peroxide just a normal water with one extra oxygen if you cannot remember the formula if you cannot remember the name doesn't matter so in H2O2 this is another special case in H2O2 the O here it's negative one okay the O is 91 other than that oxygen is always always always negative too okay other than that oxygen is always always negative okay example okay let's say c2h5oh okay so you this oxygen what is the oxidation number this oxygen what is the oxidation number somebody type in for me very good not negative two right because this is not the special case this is not the special case okay let's say another one okay all right Zing carbonate wow we have three oxygen here so this oxygen what is the oxidation number what is the oxidation number for this oxygen very good negative two okay what if I have this o three o Three core O Zone not in the syllabus okay but what if they ask you what is the oxidation number for the O in the O3 fantastic zeroa why because only got Oma only one species you are element so when you only have one species your element when you are element zero as simple as that yeah so very good okay so guys seems that you you guys have some some good ideas so if anyone already get lost if you already get lost if you cannot follow can you access in the chat box if you cannot follow already you feel very confused you can type the X okay okay no worry we are going to the last Rule and that is the last thing for today okay I'm not going to put too many things for you or else you just cannot take it okay I'm not going to put too many things for you or else you just cannot take it okay so let's look at rule number four which is the last rule already the last rule already yeah so the last rule that we can see is this okay the last row is this okay or see they shown number oxidation number four hydrogen just now we have oxygen now we look at hydrogen hydrogen the oxidation number is always always positive one hydrogen is always always positive one except again two special cases okay the two special cases I'll talk about this in a short while but let's look at the normal cases let's say normal case water water do you have hydrogen yes so the hydrogen here it's last one you see it doesn't matter how many age you have as long as you have H you have plus one so let's say we go for something different okay let's say we go for sulfuric acid sulfuric acid also got hydrogen right all the hydrogen here is last one let's say we go for hydrochloric acid hydrochloric acid also got hydrogen right so it's plus one okay so let's say we go for some uh very weird substance let's say we go for some other uh weird substance let's say we go for ch3 c 2 H 5 o h so this Furler is ethanol you will learn this in your form four form five chapter two so this further is an alcohol so this product got hydrogen these hydrogen also plus one these hydrogen also plus one okay no matter here you've got five hydrogen or here got one hydrogen don't care as long as you have hydrogen is plus one that's it very easy hydrogen always plasma oxygen always minus two except special case okay so what is the special case we have the first special case is H2 hydrogen gas hydrogen gas again of H2 both of them are H only one species so you are element again when you have element it is zero line you know when you have element you are zero another special case which is super super rare in exam as well which is called metal hydride no need to memorize a metal hydride means metal combined with hydrogen when metal combined with hydrogen you get metal hydride okay so when you have metal hydride okay so like this okay let's say we have I change color I use green color sodium is a metal combined hydrogen magnesium is a metal combined with hydrogen aluminum is a metal combined with hydrogen so when you have metal combined with hydrogen you call it metal hydride so in metal hydride all the hydrogen here they are minus one other than that hydrogen always plus one no worry this one's super super rare in eczema super super right in exam so it's good to know like it's good to know about the chances to be tested is super low very very low okay so by using these four rules now you can get majority of the oxidation number okay you can get majority of the oxidation number already okay so now let me show you using two examples how to use the oxidation number to do the to do the Apple to Apple comparison so let me use two examples to show you how to use the redox so how to do the Apple to Apple comparison by using uh these are so called uh oxidation number method okay I start with easy one person f e 2 plus plus chlorine become two chloride this one put two this one put two f e 3 plus okay so no need to memorize just show you only here so now let's say you have this question can we use oxygen method no there's no Oxygen at all can we use hydrogen method no there's no hydrogen at all so now we have to use oxidation number method so when you want to do oxidation number method first and foremost first of all you need to lease out the oxidation number first papers first of all please list out all the oxidation numbers you need to list out all the oxidation numbers okay on the left and the right so let's can we do it together so what is the oxidation number for fe2 plus here guys what is the oxidation number for fe2 plus anyone can type in the checkbox and let me know okay so some people answer zero wrong why this further got charged when you got charged you are iron so iron the oxidation number copy the charge rule number two so there are many of you type only two which is wrong remember I say what oxidation number always need to type the sign you must put the sign e even though it is positive so it is positive two it is positive to what right so not zero huh why is not zero because you've got charge when you got charged you are iron when you are iron the oxidation number must follow back the charge okay all right next one what is the oxidation number for the chlorine here what is oxidation for the chlorine here okay very good zero one because this chlorine is one species element so it's at its element element is zero rule number one very good what is the oxidation number for this chloride what is the oxidation number for chloride here fantastic negative one remember when you have charge you are iron when you are are you on I will copy back your charge negative one okay so some people say so I've got two in front only two times two are no need remember I say what all the number in front only for balancing purpose or the number in front only for balancing purpose so what is the oxidation number for fe3 plus so this Furler got charged oxidation number copy the charge last three I must put the plus if you only put three is wrong so remember oxidation number must always show the sign despite it is positive or no matter it's positive or negative you need to show the sign very good so once once you lease up the oxidation number then only you do your Apple to Apple comparison they only do your Apple to Apple comparison so let's do it okay first Apple fe2 Plus compared to fe3 plus because you can see something in common right so plus two to plus three what you can say oxidation number plus two to plus three so oxidation number we don't say gain or lose one oxidation number number you don't gain or lose you don't say I gain a number I lose a number no you can say you gain oxygen you gain hydrogen you lose oxygen you lose hydrogen so oxidation number normally we use increase or decrease plus two to plus three increase so oxidation number increases o n stands for oxidation number okay oxidation number increase so according to the oxidation number method that we learned earlier on today look back okay according to oxidation number method when the oxidation number increase means plus so it is oxidation processed okay so you know already okay what happened so it undergo Ox see they shouldn't process so when you undergo oxidation process who undergo oxidation process this follow fe2 plus so fe2 plus undergo oxidation process when you undergo oxidation process fe2 plus it is opposite reducing agent okay so next one another Apple to Apple comparison so this apple compared with this apple obviously zero to negative one what happened number decreased right according to number line 0 degree one decrease right okay so you can see the oxidation number decrease so oxidation number decrease means reduction so who undergo reduction this parallel chlorine undergo reduction so when chlorine undergo reduction you will be oxidizing agent you will go opposite as simple as that okay so guys let me know in the chat box are you okay with oxidation number method so far not very hard isn't it okay I mean okay not very hard okay now what if I increase the difficulty a little bit okay so let me see okay hi there is all the agent on the reactant side yes all the agent here will be on the left hand side here because you always compare left to the right Mark so you always focus on the left so all the Asian oxidizing agent reducing agent they're always on the left it's never on the right because you never compare right to the left okay so that's why you always focus on the left all right good question Haider okay good one all right so now this is where we straightforward okay so now let me show you how I can make it a little bit more confusing not hard just slightly more confusing just slightly more confusing yeah just look at this and then we do two parts here question then we are all done with today okay give me 10 minutes okay give me 10 minutes to finish off with uh today lesson yeah right so let's say we have zing and then we have bromine and then we have zinc bromide okay so let's do it okay let's do it okay so zinc and bromine becomes Zing bromide okay now can we first list out the oxidation number so let's list out oxidation number and I would like to ask you all okay to help me with this so what is the oxidation number for Zinc anyone can help me what is the oxidation number for Zinc okay zero R okay not plus two okay not plus two because you only get plus two when you have charge you don't have charge at all so if you don't have charge you are not an ion you have only one species you are element so its element should be zero okay so anyone can tell me what is the oxidation number for Bromine anyone bromy okay very good zero up because the bromy only got one species right you only have BR nothing else so you are element so when you're element you are zero very good guys come on the last one what is the oxidation number for Zinc on here the right hand side what is oxidation number for Zinc on the left hand on the right hand side okay I saw two plus I saw Zero any other answer zero plus two what else plus one last two okay now listen carefully yeah listen listen listen listen listen listen carefully I say five times so important listen carefully so The Zing here can it be zero no you are zero when you are element is the zinc one species here no Zing combined with BR you have two species here so when you are two species you are obviously not an element so it cannot be zero do you know the charge of zinc yes they purposely don't show you the charge but you should know it Zing bromide okay do we know what is the charge for The Zing yes Zing is Zac and two plus isn't it you learn this back in your form four what is the charge for bromide guys we are what minus right hold on okay so you don't expect they will spoon feed you give you the charge every time no sometimes which is most of the time they are not going to give you the charge we should have to find it out yourself okay you have to find out yourself so Zing broma is made by Zing z n two plus bromide b r minus so when you know the charge of zinc can we go for the oxidation number yes the charge and oxidation number is the same plus two are not two plus oxidation number the charge comes ahead of number what about the bromide so bromide we know it is BR minus so BR minus BR minus oxidation number copy back the charge negative one okay so guys let me know in the chat box are you okay with the listing of oxidation number if you are okay type okay if you're not okay Type X this is very very important okay this is very very important okay I want to I want to I want to make sure everyone's okay because this is exactly how the question will be tested in SPF this is exactly how they ask the question for SPF okay they are not going to give you all the charge money you have to find it up yourself okay but after you lease out the oxidation number then you can do your Apple to Apple comparison so let's look at it zinc compare with Zinga pronoun zero to plus two oxidation number shoot up right so oxidation number increased according to the table we learned today oxidation number increase is oxidation so zinc undergo oxidation so when zinc undergo oxidation zinc will be the opposite thing reducing agent okay so let's do another Apple to Apple comparison which is the bromine bromine compared with Romina Apple to Apple zero to negative one zero to negative one the oxidation number went down decrease so oxidation number decreased so these follow bromine undergo reduction isn't it okay when oxidation number decreases reduction so when undergo reduction so the bromine it is our oxidizing agent that's it okay so that's exactly how it works okay so to finish off with today lesson so let me show you the trial exam paper let me show you the trial exam paper so that you can see exactly how to apply it so I will do two questions for you two question with you then we were all done with today's lesson so one question from Penang one question from mrsm okay right both are trial exam questions which are good quality questions so first of all what is the oxidation number change for hydrogen so hydrogen they only ask hydrogen focus on hydrogen on the left and the right so hydrogen can release out the oxidation number okay on the left hand side h plus so h plus got charge is iron when you are ion oxidation number follow the charge plus one okay so what is the oxidation number for hydrogen on the right this hydrogen only have one species is element element is zero isn't it remember element is zero okay so plus one two zero as simple as that last one two zero answer c yeah answer C next one okay what is the change in oxidation number for chlorine so probably only focus on the CL here so on the left hand side the chlorine here anyone can tell me what is the oxidation number for chlorine on the left on the left what is oxidation number of chlorine very good zero one because the chlorine here only have one species only got CL nothing else so it's element element is zero okay now anyone can tell me what is the oxidation number for chlorine on the right hand side well done very good negative one Changi not one minus ah minus one one minus is the charge oxidation number is minus one remember oxidation number the side must come in front of the number so please don't mess up charge and oxidation number is it okay can I all right okay so negative one because we know fecl3 is made by F E and cl we know the CL the charge is minus very good okay so it's what 0 to -1 0 to minus one and of story okay so with that being said with that being said we are all done with whatever thing we need to learn today so let's take one minute to do a summary so today what we have left today we started with the first chapter of your form five chapter one up from five chapter one the longest chapter we will spend four months we will spend four months in this chapter alone if we are faster maybe three months okay all right so you need to know what is redox oxidation and reduction these two process must happen at the same time okay so we have four method to find out the chemical reaction is oxidation reduction so make sure you know the formatted and how to memorize same letter put plus different letter put minus okay so this table is super duper important must know this table so make sure you know we today we learned oxygen method today we learn hydrogen matter and today we learned oxidation number method which is good luck okay all right so you must able to do Apple to Apple comparison do the Apple to Apple comparison which is very important choose one apple on the left one apple on the right you cannot compare left and left cannot you cannot come back right and right cannot must be left and write okay Sometimes some apple you will compare two times sometimes the same Apple you compare two times sometimes some of the Apple you don't compare at all which is okay yeah and the most important one is oxidation number method because this is super popular in SPF so you must know for rule number one if you have one species you are element your oxidation number zero rule number two if you have charge your Ion oxidation number of the ion same as the charge rule number three if you are oxygen your oxidation number is always negative two except you are O2 which is element or you are H2O2 hydrogen peroxide if you are hydrogen peroxide the O8 negative one rule number four oxidation number of hydrogen is always plus one special case when you are H2 hydrogen gas you are element so zero when you have metal combined with hydrogen you are methyl hydride the hydrogen here is negative one other than that hydrogen always always positive one okay so I need your feedback so guys can you please let me know in the chat box how's everything for today how is it okay not very hard is the name okay you follow the steps you follow exactly the steps I told you you will be fine so for the first few lessons I'm not going to give you a tutorial but after that I will let you to do tutorial I'll give you three to five passion food to do not too much that make you very stressed but you must always do some question one okay because I know if I'm not giving question it's very hard that you will take initiative and do on your own very hard so I'll give you a few questions just help you to really test your own understanding right but not for today okay after three to four more lessons and only I start to give you a few questions as you know your homework or tutorial okay so you see this is the way that we will learn in your form five we learn something and directly we go to look at the past year question we look at past year question we look at trial exam paper those good quality questions so you will know exactly what what you learn and how you apply those Concepts in the real examination I think you're learning in that way is much more effective than pure reading okay so I think that's all for today all right so I'll see you guys again by next week yeah