Hello my dear students, welcome back to your favorite channel Magnet Brains. I am your science educator Dr. Muskaan and students, Magnet Brains welcomes you. Here you get free education from kindergarten to class 12. You don't need any kind of transaction payment students because Magnet Brains provides high quality education, that too free of cost.
Magnet Brains English medium channel is available on YouTube as well as Hindi medium channel is also available. If your friends are from Hindi mediums then go and tell them about Magnet Brains that Magnet Brains provide free education to Hindi medium students Magnet Brains provides many courses like UP Board, MP Board, Bihar Board, Rajasthan Board, Delhi Board, CBSE Board as well as spoken English, Vedic Maths, Crash courses Magnet Brains e-books and notes are also available Click on the link given in the description box or you can visit magnet brains website www.magnetbrains.com and there you just have to click on grab e-notes option and as soon as you will grab you will get all lectures, daily practice papers, customized videos, topic wise, subject wise everything will be available magnet brains is available in instagram, whatsapp, youtube, twitter, facebook, telegram, everywhere but you have to like, share and subscribe magnet brains Stay updated with my videos and if you have not liked my video yet, then like it first and then we will start our session. So today's session is on a very interesting topic which is coal for class 8. And students in today's session we will see what coal actually is, fossil fuels, how coal was made, how it was formed, what are its uses and how we will see the whole story of coal in today's session.
So without any further delay, let's start today's session. First of all, let's see what coal actually is. So students, coal is a hard black color substance which is thousands of feet below the earth. So what is coal? Coal is a black...
Now students, it is not so hard that even if you hit it with a hammer, it will not break. But it is very hard, it is like a rock, like we see a stone. So the stone is hard, but if we hit the stone from a height, then it will not break. If you throw it down, it breaks.
So coal is also hard in the same way. So coal is a black color hard substance which is found thousands of feet below the earth. Is that clear?
And how did coal actually become? It is a fossil fuel which is made of natural processes. Now students, we had studied about fossil fuels.
Let's quickly recap fossil fuels. fuels ke baare mein taaki aapko clear ho jaye sari cheeze ki ye fossil fuel kya hai coal ek fossil fuel kyu kaha jata hai aur actually fossil fuels bane kese is that clear so to start coal ke baare mein detail mein ek fossil fuel ka fata fata se recap kar lete hain to fossil fuels hume pata hai aise substances hai jo kese bane natural processes se bane to ye cheeze natural processes se bani or kaisa bani by decomposition of plant dead plants and animals the dead plants and animals. So, all these things are made of dead plants and animals. And after their decomposition, they got buried thousands of feet below the earth. They got buried.
They got accumulated. So, what is this? Basically, buried flammable substances. And why do we call them flammable? Because they easily catch fire.
And why do we call them buried? Because they easily catch fire. thousands of feet have been dug, so things that are made of natural processes due to help of dead plants, animals, because of dead decaying when they decompose and they become buried and they are flammable. And that's why we call them fossil fuels. So we saw examples of fossil fuels.
What are they? Coal, petroleum and natural gas. Is that clear?
So this was an outline. But actually what happened? So students you just have to know that earlier when only water earlier only water and tree used to happen. What used to happen? bohot saara paani aur bohot saare ped yeh mai baat kar rahi hu kab 300 million saal pehle yeh mai kab ki baat kar rahi hu 3 million years ago is that clear so 300 million years 200 million years ago, there was only water and trees.
Now, these trees will be dead someday. Now what happened? As soon as this tree started to die, where did it go? Inside the water. And students, at that time there were a lot of storms and hurricanes.
Hurricanes, landslides because natural processes were at peak. So what happened? The tree which was normal also went into the water due to storm. So basically the dead plants went into the water.
And the legend. But the right plants, because of the strong storm, hurricane, landslides, they also went into the water. Now what happened? All these trees and plants went into the water. But what is present under the water?
Earth crust. So where did all these dead things go? Where did all these dead plants go?
In the earth crust. things went into the earth crust. Now students as soon as they went into the earth crust, their decomposition started.
What started? Their decomposition. Now we know that they went into the earth crust. Now more flood came.
Okay. More water came. What came with water?
Rocks, sand, minerals. So all those things accumulated on them. So what accumulated?
sand, minerals, all these things accumulated on them. So they got more and more stuck. You imagine that you are a pot, you have put a stone at the bottom of the pot.
Now you keep putting sand on that stone, and keep putting, and keep putting, then that stone will keep going down. In the same way, these dead plants, because natural processes were going on on them, so rocks, sand, minerals, all these things, All these things started to get together. As soon as all these things got together, they went further down.
And you will be amazed thinking that they went 1000 feet into the earth. Now, they went 1000 feet into the earth and from above, their rocks, sand, minerals, all these things came. So what will happen student?
They get cut off from atmospheric oxygen. Now, the oxygen that we to take a breath, they did not get it because of that they got cut off. It is 1000 feet below the earth, so the cut off of oxygen and we know that there is very high temperature and high pressure inside the earth due to which the formation of fossil fuel happened and how it happened? because of decomposition of dead plants and remains is that clear? the moment they get rocks, sand, water, minerals what happens?
their oxygen is cut off and their decomposition is incomplete that is why we call it partial decomposition and because of partial decomposition the things we get what do we call them? plant remains. So, in which the plant remains were converted?
In fossil fuels. And why do we call them fossil fuels? Because because of them we produced energy.
That is why we call them fuels. Is that clear? So, this is an overview to explain how they were formed.
Now, let's come to our fossil fuels coal. So coal, as I told you, what was it? It is a hard rock which is black in colour and mainly it is made of carbon. Now you tell me that fossil fuels are made of carbon. actually made from?
Plants. Plants are mainly made from? Carbon. And when these plants decompose in the earth crust, then where do they convert? They convert into fossil fuels.
So, fossil fuels are mainly made from? Carbon. Very good. Is that clear?
Because, If the plant is decomposing and converting into fossil fuels, then what will be the main constituent of coal? It will be carbon. Is that clear?
That is why fossil fuels are made of carbon. Now let's come to carbon, hydrogen, nitrogen, oxygen and sulfur. And many other things are also made by mixing fossil coal like nitrogen, oxygen and sulfur.
Is that clear? But what is the main constituent? Carbon. Because plants are made of carbon.
Carbon. When plants decompose in the earth crust, they are converted into fossil fuels, which is coal. The main constituent of coal is carbon. There are other things that make coal, like carbon, hydrogen, nitrogen, oxygen and sulphur.
Is that clear? Now the major type of coal, now coal is available in many types like anthracite, bituminous and lignite. So these three types of coal are mainly available.
Which ones? Anthracite, bituminous and lignite. Is that clear?
Let's go. Now, coal is one of the fuel used to cook food earlier. In the earlier times, you must have noticed that there used to be coal in your house.
And on this coal, we used to burn fire. What did they do? They used to cook.
They used to cook on this coal by burning it. So, in the earlier times, cooking used to happen in our homes with the help of coal. But what has happened now? Now, we use it for railway engines so that steam can be produced in it. And for many different things, it is all used in thermal power plant to produce electricity.
Basically, what do we do, students? Let me explain to you what is in a thermal power plant. How did we use coal? So here we first heated coal. What did we do?
We heated coal. As soon as we heated coal, what happened? A lot of heat energy was produced.
What was produced here? A lot of heat energy was produced here. What did we do with that heat energy?
We rotated the turbines. Now here are the rods and these rods are immersed in water. Now as soon as our coal got very hot, we used its heat energy to convert this water into steam. What did we do?
We used this coal to convert the coal into steam. using coal's heat energy and the water around the rods was converted into steam now what we did with this steam with steam energy we rotated the rollers with the help of turbines as the rollers rotated quickly what was produced? mechanical energy So what product did we produce?
We produced mechanical energy and as soon as mechanical energy was produced, we converted it to electrical energy and in this way we produced electricity from coal. So what happens in thermal power point students? We heat coal at very high temperature.
will heat at a very high temperature. What will it do? It will produce heat energy. And as soon as heat energy is produced, here are the rods. As you might have noticed at home, we use rods to heat water.
We boiled the water with the same type of rods. Boiled it and boiled it so much that the water started converting into steam. Now we used that steam on the rollers. Just like...
As we provided energy on rollers, they started rotating and they will rotate very fast. And due to that rotation, what product was produced? Mechanical energy and then we converted that mechanical energy.
In this, in electrical energy and basically because of coal, we produced electricity. Is that clear? So, this is our...
thermal power plant me humne electricity kaise produce kari coal ko heating up karke is that clear now coal is also used as a fuel in various industry or kai companies me factories me hum coal ko as a fuel bhi use karte hai is that clear so ye thes kare thode applications and ab aajate hai hum Today's most interesting part is the story of coal. How coal actually became. So students, this time I am talking about is 300 million years ago.
300 million years. hundred million years ago and us time pick a who are cut the this is paid or poor Sarah Pani so about three hundred million years ago the earth was covered with dense forest and low-lying wetlands area kya hua cut the thing yahaan bahut Sarah is the money me Bohot saare wetlands, dal dal. Kya the bohot saare? Wetlands and bohot saare ped.
To ye time hai 300 years ago, jab bohot saare wetlands and ped hua karte the. Dense forest and wetlands, yaani dal dal hua karte the. Is that clear? Now, jaise ki, hume pata hai ki aur us time pe bohot saare natural processes hui. Natural processes like flooding, landslides, hurricanes, all these trees went to wetlands.
all these trees got stuck in the mud. Now those dead trees got stuck but along with that, the other healthy trees because there was so much flood and landslides that all the trees got stuck in the mud. Now all the trees got stuck in the mud and in the water. But after going into the water, when the flood got a little cold, Now what happened is that on them, a lot of sand, rock, minerals accumulated and due to which they got stuck in the deeper layer of the earth.
Is that clear? There was a time 300 million years ago when there were very dense forests and wetlands. Now because when they were dead, they would have sunk in the wetlands. But the flood. Because of floods, hurricanes and landslides, healthy plants and plants also got submerged in water.
As soon as they got submerged in water, they were covered with soil, rock, and minerals. Because of which they got stuck in deeper layers of the earth crust. As more and more soil deposited over them, they were compressed.
dal dal ke andar dhaste chale gaye the temperature also rose they sank deeper and deeper aur kyuki temperature badta gaya earth crust ka wo aur niche earth crust ke jate gaye And you will not believe students, our fossil fuels are found 1000 feet below the earth's crust. So these plants and trees have gone down 1000 feet below the earth. Now students, basically what we got? Plant remains. Here you can see plant remains, they have gone down below the earth's crust.
Now at this point when it is 1000 feet below the earth crust, here is very high temperature and very high pressure and because of this, soil, rock and it has gone so deep into the earth crust. ki inka atmospheric oxygen say cut off oh yeah so there is no atmospheric oxygen or in k pass ko be atmospheric oxygen nahi wah So, where did these dead plants and trees convert? They converted into plant remains. So, where did they convert? They converted into our dead plants and trees.
Plant remains. And these plant remains, because of high temperature, high pressure and without any oxygen, they converted into black hard rock which we call coal. Is that clear?
Now, basically what happened? plants, trees and leaves went into water and after going into water they started to decompose in the earth crust and because so much sand, rock and minerals accumulated on them that they are not connected to the atmosphere they could not get oxygen and due to the high temperature in the earth crust, they were unable to get oxygen. temperature high pressure be have to age of plant remains a kiss me convert okay a convert okay coal may a coal basically Khabar a a hazard feet Nietzsche earth crust K coal car formation whoa and coal car formation kiss the was student plants remain say or a plant compose kiss the what the heck carbon se to mainly coal kya kisse bana carbon se or the process of conversion of plant remains into coal is known as carbonization kyunki plant ka carbon kisne convert ho gaya coal ke carbon me jaisa ki hume pata hai energy na toh firse ban sakte hai na toh destroy ho sakte hai wo bas ek form se dusre form me convert ho sakte hai. So the same carbon which plants used to produce food with the help of photosynthesis, by decomposing that energy, within 1000 feet, in high temperature, high pressure, in which natural processes converted it? In coal.
And what did we use that coal for? For energy again. So energy converted from plant to coal energy.
So energy converted from plant to coal energy. So energy can't be destroyed or stopped but one... It can be said that it can be transferred from one type to another type.
So, that is why coal is mainly made from carbon. And where did carbon come from? The plants that were decomposed, they were converted into coal.
So, basically coal will be made from carbon. And what do we call this process? Carbonization. Now, under high pressure, high temperature, dead plants got so much heat. slowly converted into coal.
And because it was so high temperature, high pressure was there, so this coal, these dead plants, they converted into coal. Is that clear? Let's go.
Now students, this process is not one night process. That in one night plant died, fell in the ground and became coal. No, this process took thousands of years to happen.
This process started 300 million years ago and coal formation happened. So this is not one night process. In these natural processes, 300 million years before when it started and now coal is formed.
So time and pressure and temperature these three things decide coal. Time is very time taking because where did these dead plants go? When these dead plants decompose, Because the temperature of earth is very high, the temperature below 1000 feet is very high, the pressure is very high, there is no supply of oxygen, so what happened? This formation happened in peat, peat is that form of carbon which formed without high pressure and high temperature. Is that clear?
So this was converted first peat, lignite and then black color k hard rock substance me jo hai coal as coal contains mainly carbon the slow process of conversion of dead vegetation into coal is called as carbonization Carbonization process is the process of the plants that were alive once, they died, or because of the flood, they went into the earth crust. This diagram is very easy. See, these are plants, these are trees. when they were alive but they died so they went into the earth now dead people went into the earth but also good people went due to flood so all these plants and trees basically they went into the earth crust in a very deep layer and after going into such a deep layer what happened to them?
high temperature high pressure and very slow time time taking process ke baad ye jo plant hai ye convert ho gaya dead remains. Now because it could not decompose because of oxygen cut off. Due to cut off of oxygen these dead remains could not decompose completely. They had partial decomposition.
It slowly converted into carbon converted into coal. So the carbon converted into coal carbon and this process was done by the plant remains. convert hota hai coal mein usko hum kaita hai carbonization is that clear up students since it was formed from the remains that of veg plant vegetation cold is also called a fossil fuels or hume pata hai fossil fuels where he fuels a job plant remains Plant remains and from which we produced energy. That is why coal is also a fossil fuel. Is that clear?
So that is why you should know about fossil fuels. It was important to know that fossil fuels are the things that were made due to plant remains in the earth crust. And the thing through which we produced energy, we call them fossil fuels. That is why coal is called a fossil fuel. Is that clear?
So I hope by now you have understood the production of coal. You must have understood the production of coal. Now let's see in detail formation of coal. The process of formation of coal is known as coalification.
And the whole process through which coal is made, we call that process coalification. The process of making coal or the formation of coal we will call it coalification. The dense forest present in the low lying wetlands got buried in the earth.
Millions of years ago and this whole story started 300 million years ago. 300 million years ago, all these plants, trees, leaves, etc. decomposed in the mud and things get stuck in the mud. So after getting stuck, it went into the earth crust and after going into the earth crust, it got stuck 1000 feet below. Soil kept on depositing and soil kept on accumulating and kept on accumulating and kept on accumulating. And they kept on being buried in the mud.
And there came a time when they were so buried that their no oxygen connection left and that is why their decomposition process was incomplete. And because there is a very high temperature and high pressure in the earth, these plant remains converted into black colour hard rock substance which we call coal. So, they converted into coal.
Now, what are the uses of coal students? Coal was used to produce steam in railway engine initially. In earlier times, you would notice that the railway engines used to burn coal and produce steam due to which the railways and trains used to run. But due to the high pollution of coal, it was stopped.
And students, earlier we used coal to cook food. Now we can produce electricity because of coal. I have already told you that.
How? First of all, we burned coal. Because of that what was produced? Steam.
And what did we do with steam? We rotated engines with steam. And we produced mechanical energy with it. And then we finally converted mechanical energy into electrical energy.
And in this way we produced electricity with coal. Is that clear? So, coal ki madad se hum electricity bhi generate kar sakte hai. It is used in industry as a fuel.
Aur kai badi-badi companies mein coal aaj bhi ek fuel ki tara use hota hai. Up students, coal ke kai type hai jese ki coke, coal tar and coal gas. To inke baare mein hum ek-ek kar ki dekh lete hai.
So coke kya hai? It is a tough, porous and black substance. Basically aisa kuch hota hai koi.
Coke is a tough black substance which is used to make iron and other metals. So the solid part of coal is coke. So you just have to remember that coal is available in three forms. So coal is available in three major forms. The solid form of coal is coke.
And what do we make from coke? We make iron. The liquid form of coal is coal tar which makes roads.
So it is used to make dyes, drugs and perfumes. We also construct roads with coal tar. And the gas part of coal is coal gas and we use it in many industries or factories like fuel.
available in three forms. Solid form is the solid form of coal, we call it coke, with the help of which we can produce iron and many other metals. The liquid form of coal is coal tar, which we use for construction of dyes, drugs, perfumes, roads.
coal ka jo gas part hai, wo hai coal gas, jo basically factories mein fuel ki tara use hota hai, is that clear? So, aap screenshot le sakte hai is flow chart ka, isse ek summary create ho jayegi aapke paas, ab hum aate hai coke pe, to coke is a tough porous, basically coke, kya hai, coke is a porous, yaha pe kai chhed hota hai coke me, isse liye isko hum porous kaita hai, to coke is a porous black. And because it is black in colour, it is almost pure form of carbon. And what is this? It is the pure form of carbon.
So, solid form of coal is coke. A coke is a pure form of carbon. Coke is used in manufacture of steel and in the extraction of many metals.
And this coke is used for many metal extractions. For that extraction means, We use coke to extract the metals which are stored in the earth apart from coal. Coke is a pure form of carbon.
Coke is a solid form of coal. We use it for steel, iron manufacturing. We use it to extract many metals from the earth. Is that clear?
So this is our coke. Yes. Now students, what was the liquid form of coal? Coal tar. So coal tar is a black thick liquid with an unpleasant smell.
That is why you notice that when the road is constructed, So when they burn coal to make coal tar, it smells bad, it smells unpleasant. Because coal tar has a very unpleasant smell. So coal tar is a thick liquid like this.
It is a mixture of about 200 substances. So, coal tar is formed with the mixture of 200 substances. Products obtained from coal tar are used as starting material for manufacturing various substances used in everyday life.
Now, we make coal tar production for many things. For example, dyes, drugs, explosives, perfumes, plastic, paint. photographic roofing material construction of the roads etc so coal tar car use application Rose Mara kids in the game a guy's other dies paints yes I achieve they hum Colta ki madad se produce karte hai is that clear interestingly naphthalene balls used to repel moths and other insects are also obtained from coal tar aur aap notice karte ho ki aapke jo washrooms ke andar white color ki mama washing basin me balls rakti hai or if you go to a resort, then in the resort, there are white balls on the washing machine or wash basin, we call them naphthalene balls.
And naphthalene balls basically protect from moths, insects, and their unpleasant smell, so that all these mosquitoes and mosquitoes, moths, they get repelled. So students, those naphthalene balls are also produced from coal tar. So coal tar is also used for the production of naphthalene balls. Basically, coal tar is a thick liquid form of coal. Is that clear?
Now gas form of coal is coal gas. So coal gas is obtained during the processing of coal to get cooked. And when we convert coal, processing of coal into coke, So when we convert coal into coke, And the gas that comes out in between, beach major gas nickel tf4h amari coal gas the coal gas cup reduce OTI a job coal convert hotel a coke may or us be Joe gas cup reduction who died us co hum cat a hair coal gas so coal gas is formed while conversion of coal into coke it is used as a fuel in many industries situated near the coal processing plants or a kite industries may use with a just boss every factories may as a fuel key form may coal gas guy use with a is that clear so teen form of coal I'm maybe he Leah solid is coke just tell me say repeat after me solid form of coal is coke joke is clearly use with a production of iron and other extraction of other metals now cold a liquid form is cold are your dice pain drugs perfumes production may use with a And when gas is made? When we convert coal into coke. When we convert coal into coke, then during this process, the production of gas is our coal gas.
And coal gas is used as a fuel in many factories. Is that clear? So I hope you have remembered these three forms well. Thank you very much. Because students, sun, water, leaves, mountains, all these things are renewable.
All these things are present in a very abundant amount in our earth, in the world. Fire, water, but the coal, petroleum, gas, what are all these? These are present in a very small amount. And because they take thousands of years to be made. They're not made.
When the process started 300 million years ago to make these fossil fuels, and now we are getting all these things, then it takes thousands of years in their production and formation. That is why they should be used very carefully and we call them non-renewable resources because their production is very time consuming. So non-renewable fossil fuels, non-renewable resources, nuclear and students coal, natural gas, petroleum, what are all these things?
All these things are non-renewable. Their formation takes a lot of time. Renewable sources, solar energy, water, rains, mountains, leaves, trees, plants, all these things are present in abundance in our earth. That is why these are renewable because we can reuse them again. We can say that there are so many of them that we have used them so they will not end soon.
But non-renewable things will end very soon if we use them too much. And it is not that we can make them quickly because the earth's temperature and the pressure it provides, the same pressure and temperature can form coal. If you want me to Why only on earth? Our science has become so modern that we can make coal on the ground.
But coal cannot be made on the ground because to make coal, it has to be formed in the same zero atmospheric oxygen, in the same high pressure, high temperature. We cannot make it on natural land or synthetically on earth. It is made below the earth and it will always be made below the earth. Is that clear?
So things that take thousands of years to make, how many years do they take? and they will not be available so easily that's why they are known as non-renewable resources so I hope you have understood everything about coal to know more educational things like this keep following magnet brains stay updated from my next video students if you have any doubt, do let me know and students magnet brains provide e-books and e-notes you can click on the link given in the description box thank you or you can visit the website of Magnet Brains which is www.magnetbrains.com As soon as you will go to the website of Magnet Brains, customized videos, daily practice papers, topic wise, class wise, subject wise everything will be available for you. Magnet Brains provides CPSC Board, Delhi Board, Bihar Board, UP Board, Rajasthan Board, MP Board, and many other courses along with education like Vedic Maths, Crash Courses, Spoken English students magnet brains English medium channel Joe YouTube available a uski satsa Hindi medium channel be available a Iraqi friends in the medium say hi to Jai you and co but I a key magnet brains Hindi medium students Kobe free education provide curtain magnet brain magnet brains whatsapp telegram YouTube Facebook Sabhi Jaga available a bus up come on it brains go like can I share can I subscribe can I just like him Hamisha get new students stay tuned happy learning and have a nice day.