10th Class Chemistry | Chemical Reactions and Equations Part 1 Explained in English

[00:00:02]Hello everyone. Hope you all are doing good. Welcome to my channel Sai Home School.

[00:00:08]I'm here to make chemistry simple, interesting, and easy to understand. So, please like, share, and subscribe for more updates.

[00:00:18]So, today we Today's session is about first chapter of your chemistry chemical reactions and equations. It is very important to understand the other chapters in class 10 chemistry.

[00:00:32]So, in this chapter we will discuss So, main important things is what are what is chemical equation?

[00:00:42]What is chemical reaction? Then balancing chemical equations. So, balancing chemical equations is very important. Most of the questions will be come from this.

[00:00:53]Then types of chemical reaction. For your board exam, major questions will be getting from this types of chemical reactions. Here you will study four types of chemical reactions under this session.

[00:01:06]Then oxidation, reduction, and redox reaction. And simple thing it is corrosion.

[00:01:12]So, let us start chemical reactions. What is chemical reaction? Or define chemical reaction.

[00:01:20]Chemical reaction is nothing but chemical change in the in which the identity of the substance it should be changed. That is what? If we take iron Here if you take iron that you should expose into the humid atmosphere means you keep it sometime outside. So, what it will become you should observe. That is chemical reaction.

[00:01:46]So, for that chemical reactions we will write in a simple way or short way by equations. That is called chemical equations. So, we That is chemical equation is nothing but short way of representing a chemical reaction. How it will be takes place, we'll see under this chapter.

[00:02:11]So, here if you take iron tava and if you left exposed to humid atmosphere, what will happen? It will get rust. So, then get grapes get fermented. It is also what changes it will be occur.

[00:02:29]That is chemical reactions.

[00:02:34]So, so few it may be chemical changes how it will be occur, we'll see by taking one example.

[00:02:40]That is here you have to take You have to take magnesium ribbon.

[00:02:48]If you take a magnesium ribbon here, you have to burn.

[00:02:54]So, you hold it with the top and you have to start burning the magnesium ribbon.

[00:03:01]So, here see if you observe the picture, here you take a magnesium ribbon, then you have have to expose here, you have to burn. So, here if you observe that, what is happening?

[00:03:15]Here some white powder.

[00:03:18]So, white powder you should be collect it in a some watch glass. So, this will be called it as magnesium oxide means magnesium what is happening here, it is chemical changes how it will be occur. See here, magnesium ribbon burns with the flame, the changes it will be into a white powder. So, you are observing this picture, it is a white powder you are collecting in the watch glass.

[00:03:52]That is magnesium oxide. It is formed due to the reaction between magnesium and oxygen in the presence of air. While you are burning this magnesium ribbon, it will be exposed to the atmosphere.

[00:04:07]So, means it will be react with the oxygen. It forms a magnesium oxide.

[00:04:15]Then, take some zinc granules in this conical flask. So, this is conical flask. Here you will observe some zinc granules that you have to take in one conical flask. Then, you have to put some HCL or sulfuric acid. Here one it is HCL or any one acid you should put it into that zinc granules. Both now here you have zinc granules and sulfuric acid. So, here you can observe evaporation of gas. You can get it here.

[00:04:57]So, in this chemical reaction, while occurring the chemical reaction, what helps to determine whether a chemical reaction takes place or not? If you observe this also, what will happen?

[00:05:09]Then, how do you know whether it is a chemical reactions takes place or not?

[00:05:14]So, if you take a water that it will be converted into a water vapor.

[00:05:21]Or, if you take a ice, you keep it it for a room temperature, it will become a water. That you can see through your eyes, then you can know that that it state change its state, then it will be physical change.

[00:05:34]Here, how we will observe chemical reactions are taking place or not. One it is change in its state.

[00:05:42]See here.

[00:05:44]If you observe that, then change in its color. Then, evolution of gas here it will be observing. Then, if you touch the conical flask, so you added a acid, no?

[00:05:56]So, the temperature of this conical flask may be changed. So, by using these four changes you can know that there there will be a chemical reaction taking place.

[00:06:14]So, then what is chemical equation? We suddenly said, no?

[00:06:18]Short way of representing a chemical reaction. What is the process we had taken here? It is very difficult to write everything. We have to take magnesium ribbon. You have to expose into the air. Then, you have to burn.

[00:06:36]You will collect a powder, white powder. That and all it is not good way to write or it is difficult to write. So, that there is a short form we should write. So, what we are doing is we have to take a magnesium ribbon. It will be What is happening? It will be exposed to It will be react with oxygen. It forms a magnesium oxide. That it is simplest way to do this, write the form of word equation.

[00:07:06]This is chemical equation.

[00:07:10]So, the substance that undergo chemical change in this in the reaction. Magnesium and oxygen are the reactants and a new substance that is magnesium oxide formed during the reaction as a product. So, what we had write here is that is reactants. So, reactants we will write on the left-hand side of the arrow.

[00:07:37]Product, what we are getting after reacting these two, magnesium and oxygen, we are getting a product. That is we'll write it in the right hand side. This is still be left hand side of the arrow. So, if you observe here, change in the reactants to products through form arrow placed between them. We should write the arrow between these two reactants and the products. So, the reactants it written on the left hand side. Then product will be right on the right hand side. So, how write it? We will write it chemical equation.

[00:08:20]It In this, so you have to use a symbol.

[00:08:24]So, chemical equation represents a chemical reaction. That how magnesium will be represented as a Mg, oxygen will be represented that above we written as a word form. Now, it is a symbols. We should take chemical equation. O2 is oxygen.

[00:08:43]It gives rise to MgO. That is magnesium oxide.

[00:08:51]Then, second topic it is. So, if you observe above chemical equation and chemical reaction, they may ask what is chemical changes? How you will know the chemical changes occur in the reaction or not.

[00:09:09]How we should balance the chemical equation. So, you have to know the simple tricks to balance the equation.

[00:09:16]Just you have to check both product side and reactant side whether the atoms is number of atoms present in the reactant side and product side is balanced or not. You should check first. So, if it is both the number of reactants and that reactant side and number of atoms on the product side if it will be same for all the atoms then it will be balanced equation. If it is a difference in any one atom then you should balance this is that is not a balanced equation.

[00:09:52]How it will be happen? We should see.

[00:09:55]So why we should balance to equal the total mass of the elements present in the reactants and total mass of the elements present in the product side. So if you observe both the number of elements the mass will be mass also it will be balanced for the both the sides.

[00:10:21]So here one reaction we should take zinc H2SO4 it gives to ZnSO4 plus H2. You have to what I said? You have to write the name of the atoms first.

[00:10:36]What are the atoms present here? Zinc.

[00:10:39]Then here it is hydrogen then sulfur then oxygen. Now you should write the number of atoms present in the reactant side.

[00:10:52]Number of atoms present in the react side side is zinc is one product side is also one. See if you observe here one atom at the reactant side one atom at the product side. If you take a hydrogen hydrogen here it is two atoms.

[00:11:11]Hydrogen here it is a two atoms at product side. So it is now sulfur we have to take. Sulfur there is only one atom at reactant side. What about product side? Product side is also one. Here oxygen oxygen is number of atoms at reactant side is four. Number of oxygens at product side is four.

[00:11:36]Is there any balancing? We need to balance any atom?

[00:11:41]Is it same for both the sides then the number of atoms of each element is same at the both the sides. It will be same. It is equal at the both the sides, then it will be a balanced chemical equation.

[00:12:00]Then let us try another chemical equation. Fe + H2O Fe3O4 + H2. Reactant side, what are the elements present here? Product side also we have. So, what we have to observe?

[00:12:16]So, step one. To balance this chemical equation, first you have to box for each formula. See, like this. So, you should box the each atom. You should not after balancing, you should not write inside the box number of atoms. If you balance, you should not write so that first itself you should box all the atoms. All Now, list the num- number of atoms present in the elements to in the unbalanced equation. You should observe this. It is a unbalanced equation, then you should write number of the elements present. You should write. Fe it will be present. Then hydrogen it will be present.

[00:13:05]Then oxygen it is.

[00:13:07]Now, you have to write number of atoms present in the reactant side. This side, left side of the arrow, that reactant side. Fe is one atom, hydrogen is two atom, oxygen is only one atom we have. Here, if you observe Fe is three.

[00:13:27]Hydrogen is two, then oxygen is four atom. So, in it is often converted into balance the compound that contains maximum number of atoms. Where the to balance, we have to take where is the maximum number of atoms will be unbalanced. That is, if you take here only two atoms, if you hydrogen, it is two two, it is same. Oxygen, it is three atoms will we have to balance. So, that we have to take first oxygen.

[00:14:00]So, put another box, then take initially how many atoms oxygen you are balancing the oxygen atom now. You have to take initially how many atoms present in the reactant side is one. So, how many atoms present in the product side is So, reactant side, it will be present one oxygen, it will be H2O.

[00:14:22]Here, product side, Fe3O4, it contains four oxygen atoms. To balance, what we should do here? We have four, we have to balance in the reactant side. That we should what we have to do? Multiply one with the four. So, now it will be multiply four.

[00:14:40]So, you have to take equation what you have first taken by with by drawing a boxes for each formula. You should take that equation. Where we had balanced four multiplied is to the atom, that is H2O at the reactant side. That is important. You should Now, to equalize the oxygen atom, what you had done in this above, that you should write down four in front of the H2O. Not You should not write here it is a four, it is wrong.

[00:15:19]That's why we put a box for all the formulas. So, what I said before, you should not write inside the box. So, where we had balanced, so that it should be right in front of this. Here, we should write the number of atoms what we had balanced, what we had multiplied here for oxygen.

[00:15:42]Now, it is a oxygen atoms will be four.

[00:15:47]Then, second, maximum number of atoms present in this. Now, the hydrogen will become a eight here. Four, it will be belongs to hydrogen also. Now, hydrogen will be 4 * 2 = eight. 18 H2O. We have to take atoms of hydrogen. Initially, how many we have here is Now, it is four hydrogen atoms. So, if you come to the product side, there is only two hydrogen atoms.

[00:16:16]Where we should balance is now product side. What we have to do here? We have two hydrogen to become it will be eight, we have to again multiply two with the four. Now, 4 * 2 = eight. So, take write the equation. What we had balanced before for oxygen, that equation you should write. So, what we had done, where we are balancing the equation is here, product side. You have to write this.

[00:16:44]How many number of hydrogen atoms we had multiplied here is four. That you should write in the product side. Now, hydrogen is 4 * 2 = 8. Hydrogen is 4 * 2 = 8. Hydrogen will be balanced. Oxygen we have here is four. Oxygen for this year is four.

[00:17:06]Now, finally, one, that is Fe, we have to examine above equation that the which is not balanced. Now, you have to check this equation, which element is not balanced? Now we should balance this Fe.

[00:17:21]So, take now atoms of this iron. Initially, how many number of atoms present in the reactant side is reactant side is only one iron atom it will be present. If you observe this product side, number of iron atoms will be three. Three days three Fe take O4. Now we do balance. Here we have already three atoms at the product side. Here only one atom at reactant side. You should multiply with three.

[00:17:57]Now where we had done that you have to write down in the formula. So, reactant side we had multiplied with the three. That you should write here.

[00:18:13]Now you should equalize the number of atoms present in both the sides is correct or not. Here three iron atoms, three iron. Here we have 4 * 2 = 8. 4 * 2 = 8 hydrogen atoms. Oxygen we have four.

[00:18:29]Here we have a four. Finally, you should write the balanced chemical reaction is this one. So, after checking what you had done above all these steps, whether it is correct or not, you should write the finally balanced chemical equation, then you can know that the chemical reaction will be balanced.

[00:19:00]So, you have to examine whether it is balanced or not. So, if you take a chemical equation, so here what equation is more informative physical states of a reactant and product sides are mentioned along with their chemical formula.

[00:19:17]So, if you observe here the word aqueous written in the reactant side or product side is present as a solution in water. So, if you take here, it is a if you take here, it is the it is whether aqueous solution if we write if we write here it is it is if we write gas if we write here as it is a solid. If we write AQ if you write here it is a AQ. That is product side if you get it that it we will call it as a aqueous solution.

[00:20:00]Aqueous solutions means solution in water. If we take any of aqueous solution, we have to know see here glucose C6H12O6 the solution in a water that we should write here it as a aqueous solution. So, here if we write CH3OH so L we should write in the bracket we should know that it is a liquid. So, if you take CO CO carbon monoxide it is a gas. If you take a H2, it is a gas that we will represent here as a whether it is a gas, whether it is a aqueous solution, whether it is a liquid or whether it is a solid.

[00:20:46]So, try to answer for this. Why should a magnesium ribbon be cleaned before burning in air?

[00:20:53]Write a balanced equation for the following chemical equation when hydrogen and chlorine reacts to form a hydrogen chloride. You have to take a equation with the symbols, then you have to try to balance the chemical equation by using above following steps.

[00:21:15]These three you try to answer, and if you don't know, you should please comment for the answers. Then write a balanced chemical equation with the state symbol for the following reaction.

[00:21:28]You should write the symbols and balanced chemical equations.

[00:21:33]They give a solutions of barium chloride and sodium sulfate in a water react to give a [clears throat] insoluble barium sulfate and the solution of sodium chloride. You should write the chemical equation first, then you try to balance the equation. Another sodium hydroxide solution in water reacts with hydrochloric acid solution in water to produce sodium chloride solution and water. So, please try to answer for these questions and comment on the comment section.

[00:22:15]I will give you the answers in the next class. Then remaining topics, types of chemical reactions and one simple topic that is oxidation reduction and redox reaction, we will see in the next session. So, please follow the channel for more updates.

[00:22:44]Thank you for watching.