Class 12 Chemistry - Ch 1 Solution - Dhakad Batch 2027

Added: 2026-06-03

[00:00:38]Hello everyone. Hello hello how are you all brothers? Welcome to Dhaakad Batch 12th Class Science. In this class, we are going to cover the solutions of Chapter Number One of our Class 12th Chemistry.

[00:00:50]So tell me once, is my voice reaching you clearly? Please let me know that your voice, sorry, which is my voice, is reaching you. Can you see the screen clearly? Tell me once.

[00:01:08]Quickly and this session that is going to happen is your demo session. Our batch's regular classes will be arranged privately from tomorrow.

[00:01:21]Only those students who have purchased the batch will be able to attend the classes. So today's class I would suggest you to watch it completely and analyse whether you are able to understand or not whatever is being taught and then you can make up your mind that if you want to involve in the batch or not ok brother clear yes sir yes sir yes sir great great so let's start start means June holidays are over.

[00:02:02]Students do not feel like studying at all. Isn't it? No problem. Those who want to study and get good marks will definitely study.

[00:02:17]For that, let's assume that holidays will work to create an edge. If someone studies now, then let us assume that he will go far ahead of his other classes. Ok? Is it okay with the rest of his students? He will go far ahead of his colleagues.

[00:02:38]So brother, today's chapter is going to be our solutions. What are the solutions? Now you will think something Sir, solution in Hindi means that I had read that a solution to something has been found.

[00:02:48]Ok? The problem got solved.

[00:02:50]Ok? It is a case of something but the meaning of the term solution in our science is different. Here our solution means any mixture of any two things. Ok? When two things mix together, there is a solid inside the liquid like water. If I mix salt in water, what will it create? A solution. Ok? So, regarding the solutions, there are different types of solutions and we are going to discuss about all of them. We will read the chapters one by one to know what the solutions are. Ok? Then we will study the properties of solutions.

[00:03:26]How many types of solutions are there?

[00:03:28]Then we will bring the solution to the concentration level and how we will measure its concentration.

[00:03:33]What are our methods? Solute. What depends on the solvent? Then we will study solubility.

[00:03:40]After solubility, what affects solubility? Will you increase the temperature? Will solubility increase or decrease? What will happen if the pressure is increased or decreased? So these are many things which you might notice in our day to day life also.

[00:03:56]So today we are going to cover all those things in this class. So are you ready? Are you ready? Let us go.

[00:04:12]So our term is solutions.

[00:04:16]Ok? Now this solution term, what is it to us? There is a mixture.

[00:04:24]What is? Mixture. Ignore the Writing Guys.

[00:04:28]Ok? Pay attention to what I say. So there is a mixture. Now what is a mixture?

[00:04:32]Our mixture is made from any two components together. Ok? Now suppose there is water. Now what will happen when I mix salt in water? A mixture will be formed, right? Solute plus solvent of two things.

[00:04:45]One is solute.

[00:04:48]Students who have not studied are starting from the very basics. One is solute and the other is solvent. Now you will tell me sir what is salute?

[00:04:55]What is a solvent? So the solution that we get is ours which is in less amount.

[00:05:00]Ok? Which is in small amount and solvent which we have in large amount. Take the example of salt plus water. So there is more water in quantity. A full glass like this bottle. Ok? There is a water bottle.

[00:05:15]Now if I mix one spoon of salt in it, is the amount of water more in comparison to the salt? Definitely yes.

[00:05:24]So what will happen to my water?

[00:05:26]Solvent. And what will happen to the salt? Solute.

[00:05:31]Ok?

[00:05:34]Let's go after that. Read line by line.

[00:05:42]Tell me once, do you want to read it line by line or should I teach it as per my wish?

[00:05:47]Will you read it line by line? As you wish. If you tell me line by line, I will read it to you line by line, brother. Ok?

[00:06:01]Read Hum Hum Hum or Normal. Okay, I will teach you normally, it will take a lot of time like this.

[00:06:05]Ok? I know the main parts and what needs to be done from where. Ok?

[00:06:09]We have understood that the normal solutions are a mixture of two or more pure substances in our day to day life. Ok? After that as you can see here. Ok? Now that's our brass like any of ours. Ok? Brass is a mixture of what? Brass is our mixture of copper plus zinc. Ok? Both of these are different from our German silver. Like what did our copper and zinc plus nickel become? My German became silver. Ok? So this is a solution but two types of components are present in one. There are three types in one due to which their properties have also become different.

[00:06:50]Ok? Then after that comes some term of our parts per million. Now what is this, sir? I will tell you in the coming future, there is a separate topic on this. In that I will explain what are parts per million? Let's look directly at our main concern, which is the types of solutions. What are the types of solutions and how many types of solutions are there? Ok? There are types of solutions.

[00:07:17]Absolutely they are. Ok?

[00:07:19]First is our first is homogeneous.

[00:07:24]What is? Homogenous. And the second one is our heterogeneous one. Now you will tell me sir, what is different in this? What is the difference between homogeneous and heterogeneous mixture?

[00:07:35]Ok? Now there are many students who have studied very well. They easily come in the ninth class, homogeneous and heterogeneous. But still let me tell you what is the difference between homogeneous and heterogeneous. Homogenous means a mixture in which the components remain the same throughout the liquid.

[00:07:57]Like if I mix salt well inside this bottle. It cannot happen that brother, my salt got mixed in just this much. Salt was mixed on top.

[00:08:09]No, if the salt is mixed then it will dissolve evenly in every part.

[00:08:16]Ok? So the solution formed of that type will become a homogeneous mixture. Ok? If I collect water from here, I will find the same amount of salt there too. Even if I mix it from the bottom, I will still get the same amount of salt. But what will happen if I mix a spoonful of sand inside this bottle?

[00:08:34]Even after mixing, the lighter particles will remain suspended in our liquid. But our normal heavier particles will be sand. Ok?

[00:08:47]They will settle down at our bottom.

[00:08:51]This means that the amount of solute I have here will be less as compared to the bottom.

[00:08:58]So the concentration of my components or the overall mix of my components is not the same through out the liquid.

[00:09:07]So we call such liquids, such solutions or such mixtures, we call them heterogeneous. Is it clear?

[00:09:19]Well, after that our mixture becomes two and two is more than two.

[00:09:28]Ok? There are two or more two components within which homogeneous. By homogeneous mixture we mean that its composition and properties are uniform throughout the mixture. The properties and components of the entire mixture will remain the same.

[00:09:44]Generally the component that is present in the largest quantity is non-as solvent. Now I had told you that the one which is in large amount, whose amount is more.

[00:09:54]Ok? The one which is more in quantity is called our solvent. Ok? And the solvent itself determines what the physical state of my solution will be.

[00:10:05]Now look, there is more water here. If I mix salt in it, there is more solvent, then what kind of solution will it be? It will come in liquid form only.

[00:10:16]But it should happen that my solvent is, let's say, sugar. Ok? And what should I mix with it? Should I take more sugar? What will happen if I take less water? And I keep heating it. Let me keep heating it. It will come in liquid form but after some time it will turn into crystallization form. So the solution that will be made at that time will be of a different type. Many examples have been given in your chapter.

[00:10:44]Ok? Now look at this type. Ok? On these I will tell you what type of mixture will be formed if I keep gas as solute and also gas as solvent.

[00:10:56]We are going to cover all these things one by one.

[00:10:58]But in the coming classes, we are going to focus more on the examiner's favorite topics, from where the examiner tries to ask maximum number of questions.

[00:11:08]This is your intro class. In this we are just introducing you to chemistry that yes, these are your chapters. You might have studied it in schools also. Ok? This is the first chapter. By now, two-three of your units might have been completed.

[00:11:22]Tell me once, have you completed this chapter in school? Please let me know. Have you studied this in your school? This is either not read or not clear.

[00:11:36]Ok? So one more second yes one more component present in the solution other than solvent are called solute. Now, apart from the solvent, whatever is mixed up inside the solution, whatever is mixed, what will it be called? Solute. And this is water.

[00:12:03]I should add one spoon of salt to its water. Let me add a spoon of sugar.

[00:12:08]I will mix one spoon of copper sulphate.

[00:12:11]I will mix one spoon of sand. So what will all of them be called? All of them will be my salutes. And what will the mix up, the mixture that will be made of them be called?

[00:12:20]My solution.

[00:12:22]In this unit we shall consider only binary solutions. Now what are binary solutions brother? Now you will ask sir what are binary solutions? Binary solutions are those that have only two components. What's up? Only two components. Meaning that if there is water and salt inside this water then it is a binary solution. If it becomes water plus salt plus sugar then it will no longer be a binary solution.

[00:12:51]Is it clear?

[00:12:58]Tell me once, are you still able to understand or are you just getting a bouncer from what I am explaining.

[00:13:05]Is Sara still so basic? Is this becoming clear to you? Then we move on to our types of solutions.

[00:13:19]We know that it feels so good when there are less students in the class, then whatever message you send, it will be received very easily, suppose any student has a doubt, then it will be very clear to us that yes, this is the student's, but when there are classes, suppose there are 100 students in a class, then the chats go so fast that even we are not able to pay attention that brother, what is the doubt of the students, what happened, but right now I can see that you are saying yes sir, yes sir, okay brother, let us now see what are the types of solutions, see there are three types of solutions, one is my gaseous solution, second is what is liquid solution and third is what is solid solution, now due to what is it gas, due to what is it liquid, due to what is it solid, their state depends on my solvent, how is my solvent?

[00:14:24]What is the component that is in large amount? If it is in gas form then my solution will become gaseous. But if my solvent which is in large amount is liquid then my solution will become liquid. And if my solvent is in solid form and the rest is in any other form, then it will not make any difference to the solute.

[00:14:45]So the solid solution that comes out as mine is that type of solution, see if I have solute as well as gas, my solvent as well, what is gas, now sir, its example is your mixture of oxygen and nitrogen gas, wait a second, what is your mixture of oxygen plus nitrogen, now look inside the air also, in air we know that there is 76% nitrogen, 21% oxygen, so 76% nitrogen is a large amount, 21%, suppose if we take 100 grams of air, we will get 76 grams of nitrogen in it and what will we get for 21 grams of oxygen, so if we compare both of them, one is in large amount, one is in less amount, but both are gaseous and what is my solvent, mainly gaseous, so what type of solution will my solution become, gaseous, but if I mix liquid inside the gas.

[00:15:45]I should have more gas. Ok? And if there is less amount of liquid, what is formed at that time? For example, chloroform is an example of this. Ok?

[00:15:54]If we mix nitrogen gas with chloroform, then that gas is my solvent. There is a large amount of gas and solid is mixed inside it. What happens if we mix solid in small amount? Like our Cam4 in nitrogen gas. What is Cam4? It is a comfor. Have you seen Kapoor?

[00:16:15]Ok? At the time of worship, at the time of havan, it is like a solid tablet of white colour. It is called camphor. Ok? And its special thing is that it directly converts from solid to gaseous form.

[00:16:27]It does not come inside the liquid. Will you tell me once? The process by which a solid directly turns into a gaseous state is known as non-age. Let's see who will tell first. A process in which our solid directly converts into gaseous state.

[00:16:42]What is this process called? Let's see brother.

[00:16:53]Hum Hum [laughter] Who Will Tell? Who will tell? Even if you do n't know, there is no problem. Please tell them that sir, we don't know.

[00:17:06]Please tell us and whoever knows, please tell us, friend, don't go to Google, cheating will not be tolerated, if you don't know then accept that sir, I don't know, please tell me, I will tell you, I am here to tell you, I am here only to tell you [laughs] no answer means no one knows, see, if there is such a process in which our solid gets converted directly into liquid, sorry into gas. That process of ours is called sublimation. S U B L I M A T I O N Sublimation.

[00:17:51]Ok? This process is in your 10th class. Do n't know. No problem. No problem.

[00:17:58]Ok? Sublimation is our salt, isn't it?

[00:18:00]He also has the same property. If you heat the salt, it gets converted directly into gaseous form. It does not convert into liquid etc. Let us now consider the example of liquid solutions.

[00:18:16]Liquid solution means solvent liquid.

[00:18:18]Who will be mine for a larger amount?

[00:18:20]Liquid. Now we will mix gas in the liquid daily brother. You will definitely see this thing.

[00:18:25]Ok? Our oxygen dissolves in water. Hey, you all drink cold drinks.

[00:18:30]Ok? So when the bottle suddenly opens and a thumping sound is heard inside the cold drink, what is that sound of? That gas is mixed inside our liquid, inside water. Ok? So this will be our example.

[00:18:41]After that your Henry's Law also works on this. Ok? That brother, how much amount of our gas will dissolve on any liquid. That was told by Henry Law.

[00:18:54]Ok? Its example comes in your application, there is an example of cold drink that as the pressure increases, the solubility of our gas increases, that is why the bottles are filled with pressure, Sir, please teach from the notes, ok brother, ok, it is fine, from tomorrow I will teach from your notes, no issue, ok, no problem, from tomorrow I will teach you from the notes and will also provide you the same notes, it will be fine, right?

[00:19:23]We hum hum hum, let's go, okay. So now if I mix liquid inside the liquid, then brother, that is our ethanol and water. Ok? Now what is ethanol? Ethanol is our other name for it, alcohol.

[00:19:42]alcohol. Now what comes to your mind due to alcohol?

[00:19:47]bottle.

[00:19:49]Hey, that is the solution of alcohol.

[00:19:54]Sir, I don't know how to spell [sound of clearing throat]. No problem brother. No problem. Ok. Contains alcohol.

[00:19:59]Mix the alcohol with the water.

[00:20:01]Ok? So what will be ours? Liquid in liquid. Oh, that's a lot of things, man.

[00:20:06]Milk Now do you bring milk like this? Do you bring milk or solution? Is that milk or is that solution? Tell me, is that milk or do you bring a solution? You bring the solution. What do you bring? Solution. Because brother, will the milkman give original milk? No.

[00:20:33]What will he mix in the milk and give it to you? Milk plus water.

[00:20:39]Ok? After that, if you want to mix solid in liquid, dissolve glucose, dissolve salt in water, dissolve sugar.

[00:20:46]Whose example is all this for us? So in this case the solution we will form will be liquid.

[00:20:50]Now if my solvent is in large amount, solid solid solid, now if we mix gas inside the solid, then also a solid solution is going to be formed, if you mix liquid inside the solid, then also a solid solution is going to be formed and if you mix liquid inside the solid, then also our solid solution is going to be formed, now like the example of solid plus gas, our hydrogen, okay, mix it inside palladium, secondly our amalgam of mercury with sodium amalgam is there, brother, our mercury reacts with anything and forms its alloy. When we mix it with ourselves, we call it amalgam. Remember brother, in your competitive exams also, the question often comes that alloy of mercury is non-age amalgam. And your copper has dissolved into solid gold. Ok? The jewellery you bring is not pure gold.

[00:21:41]It is made of 22 carat gold. 20 carat to 18 carat gold. Meaning, if we assume 20, then some percentage of copper is mixed in it. Ok? So that its strength can increase because gold is soft. So if it does not have the strength to do so quickly then the jewellery will break quickly. Ok? Now suppose you got a chain made worth Rs 2 lakh. Ok? And you were wearing pure gold, 24 carat gold.

[00:22:10]What happened next? I couldn't even find you immediately.

[00:22:13]If your hand touched something or something happened, it got stuck in the button and broke suddenly and you did not even realize it and it broke and fell down.

[00:22:19]Ok? So what is mixed in our gold because of this? Copper is mixed to increase its strength.

[00:22:30]Come on brother, after that comes expressing concentration of solutions. What is? Express concentration of solution. Now you will tell me sir what is concentration? Tell me, what is the concentration of the solute mixed in me? What is the amount of solute kept? It is mixed. How much amount of component is being mixed? That depends, that depends defines our concentration.

[00:23:11]Suppose, for example, there is water.

[00:23:21]What will happen if I mix salt in this bottle? There will be some concentration. But now I mixed one more spoon. Then the concentration will become high. Again I mixed one spoon salt. The concentration increased further. I will mix another spoon. The concentration increased further. Mixed another spoon. The concentration increased further. Again I mixed another spoon. This time half a spoon got mixed. And half a teaspoon I'm doing something. It is not mixing at all. I keep mixing, I keep mixing. That half spoon is not getting mixed at all. What do you call that situation? We call that situation a saturated solution. What do you say?

[00:24:03]Saturated solution. S A T U R A T E D Saturated solution.

[00:24:15]Ok? Saturated solution means that we reach a situation where the dissolution of the solute becomes equal to the dissolution of the solute as well as equal to the concentration. Look, do you know what happens? Now the solute is getting mixed. It is getting mixed. The salt is being mixed. It is occupying the empty space between the water molecules inside it.

[00:24:40]But a time will come when all that space will be filled. So more salt will stop mixing. Why? Because the amount of salt that will become liquid after that, the same amount of salt will get converted from liquid to solid.

[00:24:54]A loop is formed.

[00:24:57]As much as it went from solid to liquid, it converted from liquid to solid.

[00:25:02]Ok? So that situation is called that our equilibrium of concentration has been set. Ok? So we ask him what has happened to our solution? Saturated.

[00:25:14]Ok? What is a saturated solution? Did you understand? Let us go.

[00:25:20]Now we can define concentration in different ways. Ok? Now I feel like telling you in terms of mass percentage. I feel like telling it in terms of volume, brother, if I measure it in grams, then in kilograms, in ml or in litres or I measure it in moles, okay, I should calculate the mass percentage, parts per milli-mole fraction, or I should calculate the molarity, I should calculate the molality, it is my wish, all these terms are used to define the concentration of something, okay, so let's study the mass percentage.

[00:26:03]Listen to these topics carefully because your numericals are formed from here. You may see a numerical in this chapter.

[00:26:11]These three, four, sorry, these five, six topics are mass percentage, volume percentage. Ok? Mole fraction, molarity, molarity, all these can give you a numerical view.

[00:26:26]Finding out the molarity will give it away. Molality mole fraction depends on the examiner.

[00:26:30]He will give whatever he wants. So what is mass percentage? What is the percentage of mass, brother, how much of my 100 is it? Now there are many students. Ok? Now you too must be expecting that the result has just come.

[00:26:50]Someone will tell your brother that I got 90% in 11th.

[00:26:55]Someone will say I got 95%. Ok? Now what is that percentage? That means, to compare with 100, suppose there is a student who gets 490 marks out of 500.

[00:27:14]Ok? So how many will come out of his 100?

[00:27:17]So to find the percentage, we multiply it by 100. So cut it. One second yes zero to two zeros cancel out 5 * 1 5 is how much? 5 * 9 45 How many survived? 4 5 * 8 40 so what percentage did it become? That student got 98%.

[00:27:42]So using this method we can also find out the concentration from the mass percentage.

[00:27:48]Like the mass percentage of a component of a solution is defined as mass percentage of a component that brother, I mixed one spoon of salt in it. So how much of it got mixed in it as per percentage? That's what I have to tell. But what quantity do we want to buy? By month. So the mass of the component of the solution upon the total mass of the solution. Suppose this example is also given. Well, I was just going to give an example. He has already given it.

[00:28:18]If a solution is described by 10% glucose in water. If someone said that brother, there is a solution in which what is 10%? Glucose is inside the water. By month by month. Ok? So it means that brother, there is 10 grams of glucose in it and what is there in 90 grams of it? Water which made my overall solution 100 grams. So if I say in 100 grams that this is 1 liter of water. Ok?

[00:28:51]If I say that I have mixed this much in 1 litre of water, then that volume will come as volume percentage as per litre.

[00:28:59]But let me tell you that brother, there was 1 kg of water and there is 100 grams of water and I have also mixed salt in it myself. Now suppose I have mixed 10 grams of that salt, then what is the total amount of 10 upon it? Ok? And by adding 100 to Inu, you can calculate the percentage. Let's say 1 second. Yes. Accept it. Now let me take an example of this.

[00:29:26]This was my water 980 grams.

[00:29:34]What is this mine?

[00:29:37]I mixed 20 grams of NaCl (Sodium Chloride) in Water Plus, so you must know that the salt that you eat in our house is the salt of our country. Ok? I mixed 20 grams of NaCl.

[00:29:53]So what will be my total for both of these?

[00:29:59]100 grams. What is this mine? Solvent.

[00:30:05]What is this mine? Solute.

[00:30:09]And what did this total become? Solution.

[00:30:14]So if I say find out its percentage in this solution, what will it be?

[00:30:21]How much was total made in 20 upon? 100 multiplied by 1000, two zeros to two zeros cancel out, one zero to one zero cancel out, so what will I get? What is my 2%?

[00:30:36]Salt is mixed in this 000 grams of solution. Did you understand?

[00:30:45]1 second. Keep your voice a little soft. Okay brother, okay okay friend, it is a little bit natural for me and you know what is happening, this is the microphone, it is right near the mouth, so because of that also you might be hearing it very loud, it is my habit, like when we study on the digital board, the microphone is placed here, so there is not much issue of voice from there, okay I will try to keep my voice down, sir, your voice is going in the math class.

[00:31:21]One second Grover to answer, not at all brother, it is running in the system. Let us go.

[00:31:45]After that now comes our volume percentage.

[00:31:52]What is volume percentage? Volume percentage is my volume percentage. Meaning the volume of component upon the total volume of solute. If it was this is 1 liter of water. This is 100 ml of water.

[00:32:06]I missed something else inside this.

[00:32:10]I have mixed 100 ml alcohol in it. Then what will happen if my 1000 ml is made? Suppose 900 ml what is mine? H2O 100 ml What's My alcohol.

[00:32:34]Ok?

[00:32:37]So how much did you make in total?

[00:32:44]1000 ml is fine. So if I say that from here find out the volume percentage of this water and give me the volume percentage of alcohol.

[00:32:52]If I have to remove the water from it, the water will come up.

[00:32:58]900 ml / 1000 ml total is 100 into two zeros cancelling out two zeros. This is my 90%age, so what?

[00:33:12]H2O And if I have to remove alcohol, how much alcohol is there? How much is the total in 1000 ml upon? Oh sorry 100 ml is my alcohol.

[00:33:23]And my total is 1000 ml solution. I will make it 100. Two zeros plus two zeros cancel out one to one so 10% becomes what?

[00:33:33]alcohol.

[00:33:36]Is it clear? What is this? This is the volume percentage.

[00:33:45]Echo is happening. Let me check one second.

[00:33:51]We're one second guys. What is a natural number that is divisible by, sir? How many exercises will we make you do today, only two, not just two, the chapter will be finished in two days, the chapter will be finished in three days, so any number which is divisible by two, not divisible by two, is also ok in sir's class, no issue, okay, let's go. Let us go.

[00:34:39]So brother, many other students will also have doubts that Sir, we have other subjects too, how will they be? Look, classes will be arranged in this manner. I am also taking your English class during the day.

[00:34:52]Ok? The class you have in the evening is in English. Ok? Also, this class of yours, which is after 7:40, will contain your subjects.

[00:35:11]This class has been kept because I have started teaching this subject, Chemistry.

[00:35:15]So if I want, I can extend this class for as long as I want. I can take this class for 1 hour to 1.5 hours. Because there will be no more classes after this class.

[00:35:26]So if my topic remains then we can teach extra. And also, believe me, I will get this chapter completed in 3-4 days.

[00:35:36]One chapter your chemistry done.

[00:35:39]Ok? Then your classes will be of Physics plus Maths, who will teach you, Sunil Sir? Ok? Then they will get a physics unit done according to each one of their own. You will complete one unit of Maths and then you will get marks for the second unit of Chemistry.

[00:35:55]So in this way your entire syllabus will be covered. There is no need to worry.

[00:36:01]Around two units will be easily covered every month by having your classes daily in this way. Ok sir. Please provide its questions in the batch group. Definitely friend, you will get notes for this also.

[00:36:27]Plus, you will not get its questions but PYQ questions which are your most important.

[00:36:38]Ok?

[00:36:40]Everything has been planned. You will get everything including your notes plus PYQs. There is no need to worry. I will give questions of last 10 years. You will get every idea about which topic the examiner is asking more questions from.

[00:36:56]Which one is Numerical asking? Which topic is his favorite? Is it clear?

[00:37:04]Yes, yes you will get everything in the batch group.

[00:37:06]Once no issue. Let 's read the volume percentage after that.

[00:37:17]Now let us come to mass by volume percentage.

[00:37:21]Now what will be the mass by volume percentage sir?

[00:37:25]Mass by Volume Percentage. Meaning, in which part does my mass reside? In grams.

[00:37:31]What is my volume?

[00:37:34]Inside ml. This is how mass by volume percentage is calculated. Suppose this is water.

[00:37:39]What is the total volume of this water? 1000 ml but in it I should say that I have mixed 100 grams of solute.

[00:37:49]Gram. Okay, right? Gram said, I have mixed 100 grams of solute.

[00:37:55]And what was my 900 ml?

[00:38:00]Solvent. So what did solute plus solvent add up to and make my 1000?

[00:38:04]Made the solution. So what is my volume? The total volume is taken from 1000. Ok? But how much salt did I have? 100 grams. How much solvent was there in Plus? 900. So this creates our mass by volume percentage. Ok? How much mass have we dissolved? Mass of solute dissolved in per 100 ml of solution.

[00:38:30]How much mass have we dissolved in 100 ml.

[00:38:33]This is our mass by volume percentage. Ok? Just remember this.

[00:38:41]Parts per million after that. Sir parts per million.

[00:38:43]Parts per million means if I picked up a part of it.

[00:38:51]Ok? And by taking a part of it, I can say that brother, out of these 1 million molecules or atoms, how many of these 1 million atoms or 1 million molecules are my molecules of my solute.

[00:39:08]So what is that quantity, the way of measuring it is called parts per million. Ok? What happens?

[00:39:17]Parts per million.

[00:39:21]So when a solute is present in trace quantity, means trace means in very less quantity, if I say that there was a whole lake and I mixed 1 kg of salt in the lake, then what will happen, parts per million, means that in comparison to that huge amount of solution, sorry, in comparison to that huge amount of solvent, the amount of solute is just nominal. In absolutely trace amounts, in absolutely very small amounts. So when I take 1 litre of water, out of its millions of molecules, I will get two-three molecules of salt.

[00:40:03]Who will own the rest? Of water.

[00:40:05]So parts per million. So it is convenient to express concentration in parts per million. Ok? The number of parts of a component and the total number of parts of all components of the solution.

[00:40:18]Suppose in this, to represent 10 to the power 6 million, sir please explain it once again, mass by volume percentage, hey look, mass by volume percentage is that how many grams of mine are mixed in 100 ml, now see, I said that brother, there was 1 litre of water.

[00:40:50]How much was it? 1 liter water. 1000 ml water see000 ml water is 100, right? Brother, I will make it 1000. Ok? And I said, what did I mix 10 grams in it?

[00:41:06]Salt.

[00:41:08]Now I put 10 grams of salt in 1000 ml solution and ask brother to find its mass by volume percentage. What will be the mass by volume percentage? My 10 grams is ok, divided by what is the total of my 1000 ml, but what should I tell you, how much is there in 100 ml, if I convert this ml into litres, then how many ml are there, if I compare this 100 ml with this, then how many are there, there is 10 in into, right, I will multiply it by 10, then it will become 100, only then will it become 1000 ml, so in the same way, how much will be mixed in 100 ml, if 10 grams are being mixed in my 1000 ml, then how much will be there in 1 ml, if I multiply by 10 / 1000, then how much will be there in 100 ml, if you multiply by 100 in this also, then 1% means that in every 10 ml, what is 1%, the solute is mixed in every 100 ml, this is mass by volume Please provide the percentage question in the batch group, we will definitely get it done, Harvansh I understood, okay okay okay okay okay.

[00:42:47]Parts per million I hope would have arrived. Let me tell you once again, brother, how many parts in a million, how many parts in a million, if I mix a crystal, a small grain of salt in it.

[00:43:03]Ok? So that would be called parts per million. That brother, how much amount of salt is there in so many million molecules? What is the amount of salt? That is parts per million. Then comes our mole fraction. It is important brother to look at this carefully.

[00:43:22]What is? Mole Fraction. Before mole fraction, you should know what are moles?

[00:43:32]What are moles? What are our moles? Moles are our given mass.

[00:43:46]What is molecular mass in Upon?

[00:43:50]What is our molecular mass called in Given Mass Upon? Number of moles. So we have to find the fraction of moles.

[00:43:56]Now I need the moles of the entire component and also the total number of moles in the entire component. If I have mixed salt, sugar, copper sulphate or anything else in it, if I get the moles of that and get the total moles of that, then from there I can find the fraction of moles.

[00:44:19]Ok? I have understood sir, okay brother Ankush Malik, okay let's do one thing, the topics that are going to start from here, like mole fraction, after that, okay mole fraction molarity, okay molarity, all these topics are connected to moles. So why don't we do these tomorrow and along with this, we will do these examples given after every question. Is this one okay? These are the questions that come 1 second after that. Ok? We will do this.

[00:45:13]Along with this, you have given examples in NCERT. The examiner gives it from here. Ok? And along with that, we will get your interest questions resolved. One two one two you will also get your homework tomorrow.

[00:45:27]Tomorrow we will discuss solubility.

[00:45:30]We will discuss the solubility of solid in liquid. We will cover all these topics. Gas in liquid.

[00:45:37]Ok? From there, our vapor pressure will come. Once vapor pressure is reached, our Henry's Law will come into effect. Most important topic of this of this chapter. The most important topic of this unit is Henry's Law. He asks again and again and again and again. Henry Law arrived.

[00:45:52]Who will come after Henry Law?

[00:45:55]Raoult's law will come into effect. Then colligative properties will come into play. Ok?

[00:46:01]So all these topics are going to come. So I want to cover these moles tomorrow. Because if I do moles, then after moles, normality, molarity and molality, these will consume your time because we will not make them superficial. We are going to do this very deeply. This is where the question arises.

[00:46:22]Ok?

[00:46:26]So we do it till here. Our parts per million. We have reached this point. Ok? I will come to the class tomorrow when we will have our private class, then we will discuss this thing once again there, recap what we have read and quickly start our mole fraction from tomorrow, okay tell me once brother, all the students who are watching, sir, was this your first class, did you understand whatever was told, did you understand friend, tell me what is happening?

[00:47:09]Tell me once, did you understand or not?

[00:47:12]And your first class was Chemistry, did you find it difficult or easy? Did you find chemistry difficult or easy?

[00:47:29][laughter] Hmm.

[00:47:38]Sir, will you also conduct question answering along with the classes? I will definitely get it done, friend. Ok? Like today we had 12th English class.

[00:47:46]So tomorrow I will make you solve the important questions of that chapter, the type of questions which are most important and you will also get their PDF inside the group.

[00:47:57]You will also get a PDF of its summary. There is no need to take tension sir, I have understood, okay Hardik Ankush Malik, it was very easy sir, great Hitesh Gangas, I have understood till now, okay brother, okay, till now it is easy, okay, okay brother, okay, from tomorrow we are going to start from here, from mole fraction, okay, we will study it deeply, so see you in the next class and those students who are watching the recorded. So brother, attend live classes daily.

[00:48:36]Ok. So bye-bye. See you in the next session guys which we are going to do privately.

[00:48:43]Absolutely. Bye-by good night.

[00:48:53]One second sir. Please send the exam coach content of this chapter to the batch group. Okay brother, absolutely no issue.

[00:49:04]Ok bye brother good night. Good night.