acid bases salt grade 10 science part8 cbse

[00:00:19]Disconnected. What? Anything important?

[00:00:26]Ready?

[00:00:50]See first you will start. Acid is already over. Now one question I'm going to ask from all of you.

[00:00:58]See Ragu is having exam. I can understand. Hashid is having exam. Where are the KB students for them? What special type of exams are there?

[00:01:09]Huh? Sleeping. Now they're thinking I will not keep class because others are having exams. Correct. Now they are in very big problem. Their mental problem.

[00:01:19]I'm going to release weight.

[00:01:22]See Deepipika why you are online Shanmati Shmati online I can understand why is online where is now look here what are bases bases are substance that taste bitter and feel slippery we know this this is one of the most simple property of base where acids are sar in taste bases are bitter in taste understood not now acids have a different texture bases are slippy Slippery. Understood? Not how braces exactly at touch it looks it feels like slippery. Understood not. Next they change the color of red litmus paper to blue. What is the change of color of pieces? Red litmus paper. It is converting to what color? Blue. Let red litmus paper to which color? Blue color.

[00:02:15]So that's the texture of bases.

[00:02:17]Understood. Not I. I'm fine. Thank you.

[00:02:19]Now come on everybody please.

[00:02:24]I hope everybody please kindly Deepika travel. Oh okay fine. Good morning Karthik everybody start giving your name please. I told you at the beginning of the class all people have to give their name who are present offline online online offline are here or rest other people are sleeping.

[00:02:50]Now look here. So we are going to talk about red litmus paper to blue. So basis converts red litmus paper to blue. Bases are converting red litmus paper to blue.

[00:03:02]That we must remember. Now what is the definition of basis? Unlike acid in acid what we have seen is that when an acid is added in water it will release what ion? H+ ion. Understood. That is called as what? Hydrronium ion because the H+ will be added with water. It will become H3+ then what it is called as hydronium ion. What it is called as hydronium ion. What it is called as hydronium ion.

[00:03:37]Okay. Lakshina, Karthik and Kavia, Shanmati, your brother is missing.

[00:03:53]He's online.

[00:03:58]Yeah, Shashwini is here.

[00:04:00]Yashika is missing and Ara is missing.

[00:04:03]So, I hope you might have understood this one. So now we are going to talk about definition of bases. In basis one simple definition is there that they will dissolve in water. Dissolve in water to give hydroxil ion. Which ion?

[00:04:18]Hydroxil ion. Where acids are dissolving in water to give hydronium ion. Bases will give hydroxil ion. What is hydroxile ion? Hydronium hydroxil. Vry.

[00:04:34]Good morning beta. Hydrronium hydroxile.

[00:04:37]Can you repeat with me? Acid will give hydrononeium ion and bases are giving hydroxil ion and that is called as O minus ion. That is H3 plus and this is O minus. Understood sin. What it is called as beta? O minus ion. Good morning Sakshi. O minus ion. I hope you might have understood this one. So now types of bases. How many types of bases are there? First we'll try to check that how many types of bases are there. Okay, some bases are strong bases and some bases are weak bases. That we know now like acid also all the acids were not strong or all the acids were not weak.

[00:05:23]Some acids were strong and some acids were weak. Correct.

[00:05:28]Like we came to know that inorganic acids the acids which are man-made they were very strong. Can you tell me the names of some of the acids children which is strong and good? Good morning.

[00:05:43]Can you tell me the names of some acid which is actually strong?

[00:05:49]Huh?

[00:05:51]H2SO4 that is sulfuric acid. Sulfuric acid is a strong acid. Well done. Next, hydrochloric acid is a strong acid.

[00:06:01]Nitric acid is a strong acid. Very good children. Come on, start saying the answers. I only got answers from Deepikash and Mati. Quickly answer Sakshi present. Okay. So, what and all acids are there? Can we can we repeat it one more time?

[00:06:20]>> Sulfuric acid, nitric acid and hydrochloric acid. So, these type of acids are what? Strong. Understood? What about the other acids which are exactly weak? They are inorganic acid or organic acid? Organic acid. So organic acids are weak acids. Understood? Or why? Because their degree of dissociation is less because what is the meaning of degree of dissociation? Very good. Well done children. Degree of dissociation means they dissolve very readily in water.

[00:06:51]They cannot what do you call dissociate completely and release H+. they cannot dissociate completely and release H+ but most of the strongest acids they're releasing H+ completely enough so hydro hydrogen dissociation is fast but there that is hydrononeium ion absolutely correct they so here the release is very fast that we must know understood or not for that called a degree of dissociation now a base is either a metallic oxide A base is either a metallic oxide. What is the meaning of metallic oxide? Metal added with oxygen oxidized. A metal which is oxidized is called as metallic oxide. Understood not like magnesium oxide, calcium oxide. Understood not sodium oxide. Understood not. So when a metal reacts with oxygen, it comes in contact with oxygen. the oxidation happens and that is called as metallic oxides. So metallic oxides are bases in nature. Not metallic oxides are bases in nature and non-metallic oxides are acidic in nature. Already we know that metallic oxides are bases in nature.

[00:08:12]Children metallic oxides are bases in nature. That's very much important to know. Next metallic hydroxide. Metallic hydroxide metal reacting with water.

[00:08:24]Understood on so metallic hydroxide that is also basis in nature or aquis ammonia ammonia added with water that is also basic in nature. So there are the types of bases we which which react with hydrogen ion of an acid to form salt and water. Understood or not? And you know that aqua ammonia which is also reacting with what?

[00:08:51]Hydrogen ion. Which is reacting with what? Hydrogen ion to form neutralization reaction. Understood?

[00:08:59]Salt and water. So when an acid react with a base to form salt and water that type of reactions are considered as or called as neutralization reaction. what it is called as beta neutralization reaction. So what is neutralization reaction? When an acid reacts with base to form salt and water, such reactions are called as neutralization reactions. Till now whatever comparison we have generated one by one, Bhnesh, good morning.

[00:09:37]Good morning Bhnesh. So now please repeat the content. I'm repeating the content for everybody. So what in all we have learned karthik today evening I want all the answers from trickle kundam children what I have taught this right now what we have studied beta bases are bitter in taste bases are bitter in taste this is first point good morning am come here front so bases are bitter in taste that is first thing the second point is the bases are oh minus releasing Understood not that is called as hydroxile ion. What it is called as hydroxile ion.

[00:10:20]So when someone will ask you you will be able to answer or not hydroxile ion and hydrononeium ion. Acid releases hydronium ion that is hydrogen ion.

[00:10:32]Correct? And basis releases hydroxil ion. Understood? Next part we have studied is now we are going to talk about some very important thing. See alkaly what is the meaning of alkaly? If somebody asked you about alkaly what answer?

[00:10:51]>> Very good. Those bases which are water soluble are considered as alkaline. See understand one thing. All the bases are not alkalies but all the alkalies are bases. Understood. All the bases are not alkalies but all the alkalies are bases.

[00:11:11]Understood? Then you will be confused about why it is considered as alkalies.

[00:11:16]Understood? So the alkalies usually shows basic behavior. What is the meaning of basic behavior beta? They will be dissolving in water. After dissolving in water, they will be releasing O minus ion. What they're releasing? O minus ion. That is called as hydroxil ion. Very slowly I have explained this part. Please children try and understand this. What did I said?

[00:11:44]The bases are releasing what? Ominus ion. What it is called as hydroxile ion. What it is called as hydroxile ion.

[00:11:57]Now we going to talk about basic oxide.

[00:11:59]Are you all ready for basic oxide please?

[00:12:03]Likita. Good morning.

[00:12:15]Pineal aroma two Russian three sham 4.

[00:12:33]Okay. Now we are going to see one reaction. Huh? So look here a basic oxide. What is the meaning of basic oxide? Metallic oxides. Metallic oxides are basic oxides. Metallic oxides are basic oxides. So now metallic oxide a basic oxide is a metallic oxide that contains oxygen ion and react with an acid to form salt and water. It's a complete type of neutralization reaction. It's a complete type of what type of reaction? Neutralization reaction. So if somebody will be asking you about neutralization reaction, what answer you are going to say? That metals non-metals which one? Metal which oxide metallic oxide what it is basic in nature react with acid. Understood not react with acid. It is exactly going to form salt and water. So what is the structure line? Acid base reaction releasing salt and water is neutralization reaction. Now a basic oxide is a metallic oxide. Can we check this one out? This is a metallic oxide and this is acid. Acid and base, salt and water.

[00:13:57]What it is called as sodium sulfate.

[00:14:00]what it is called as sodium sulfate.

[00:14:03]Na2SO4 is sodium sulfate. Another one sodium hydroxide. So when we talk about sodium hydroxide, good morning everybody.

[00:14:13]Please write your name and send. So this is what this is sodium hydroxide. So when sodium hydroxide react with sulfuric acid again this is acid base reaction and it is a type of neutralization reaction. It will give salt and water. It is again giving what beta salt and water. So what this reaction is called as neutralization reaction. Till here it is done.

[00:14:45]Metal oxide acidic or basic?

[00:14:49]Come on, write the reaction. Practice the reaction please. Na2 SO4. Come on, go for it.

[00:14:57]Na2 SO4 is a salt. Na2 SO4 is a salt. You must remember all this. Na2 SO4 is a salt. The next part Na2O sodium oxide.

[00:15:13]Na2o is sodium oxide. H2S04 is acid.

[00:15:18]H2S04 is acid. That is acidbased reaction. It's a type of neutralization reaction. Acid base reaction is a type of neutralization reaction. Acid base reaction.

[00:15:33]Neutralization reaction. I hope Karthik understood. Come on children give me thumbs up that you people understood.

[00:15:40]Deepika understood. Very good. Karthik understood. Super.

[00:15:55]Very good. Super. So I hope many people understood what is exactly acid base reaction. Super that is neutralization reaction. Na2SO4. Don't forget because last time we were doing chemical equation revision at the time of doing chemical equation pineal good morning pine again late now look here at the time of doing acid base reaction we we understood two three things at the time of doing acid understood very good super come on get ready and start attending the part please so here base acid said it is forming salt and water.

[00:16:39]So now let's talk about alkalies. Okay, alkalies. Just now I was discussing about alkalies. Alkalies are water soluble bases. The first line itself clears everything. No problem.

[00:16:53]See now please understand this part.

[00:16:55]When somebody talks about alkalies, what is the meaning of alkalies children?

[00:17:00]Alkalies are water soluble bases.

[00:17:03]Understood? Those bases which are soluble in water. So the bases which are soluble in water are called as alkalies.

[00:17:13]Understood. The bases which are soluble in water is called as what? Beta alkalies. Understood? So they and furnace O minus ion. Yes. Hydroxil ion release is there in aqua solution.

[00:17:29]Release of hydroxil ion in aquous solution. Release of what ion beta?

[00:17:34]Hydroxil ion. An alkali is a basic hydroxide. Okay. Which when dissolved in water produces hydroxil ion as the negative ion. Can I say this statement amish that all the bases are alkalies.

[00:17:52]Why I can't say this statement that all the bases are alkalies.

[00:18:00]All the alkalies are bases. Selv is telling all the alkalies are bases. Yes, I do agree with your content. All the bases are not alkalies. Why can't I say like this?

[00:18:14]>> Very good. Super. So some bases are partially or insoluble in water but all bases are not soluble in water. So there is a category. Understood not those bases which are soluble in water are called as alkalies. So water soluble and releasing O minus hydroxil ion release that type bases are considered as alkalies. Absolutely correct Shanmati.

[00:18:39]Now all alkalies are bases but all bases are not alkalies. The insoluble bases are known are not known as alkalies. Now let's talk about alkalies. Sodium hydroxide. Sodium hydroxide is a very strong base. Sodium hydroxide is a very strong base and 100% it is alkaly also.

[00:19:01]Potassium hydroxide is a strong base.

[00:19:04]Again, it is an alkal. Next, calcium hydroxide is a strong base. They are all alkalies. They are all alkalies.

[00:19:15]Potassium hydroxide, calcium hydroxide, sodium hydroxide they are releasing O minus ion. So they are strong base or they are bases which are alkalies.

[00:19:27]Understood? So now we will go to the next part.

[00:19:32]Bases will also be categorized in different categories. Okay. So first category is depending on strength. So on the strength of release of what is the meaning of depending on strength? Who can say online? Children please kindly answer me question.

[00:19:54]>> Rate of dissociation.

[00:19:58]>> Very good. S you have to say anything.

[00:20:01]Those children who are present online can you tell me depending on strength means actually what?

[00:20:13]based on degree of dissociation. Very good telling based on degree of dissociation. So we know one thing the one who release O minus as fast as possible they are strong bases. Correct?

[00:20:25]Now means the moment I will be putting the base in water they will release O minus. Understood? Metal separate O minus separate. So that's called as a strong base. Understood? They are strong bases. Depending on concentration, what is the meaning of concentration?

[00:20:48]What is your concentration means beta?

[00:20:53]>> Yes. Very good. How much amount is needed for acid and base to react properly? That's called as depending on concentration. Very good. Next.

[00:21:02]Depending on acidity. Depending on acidity. That's called as mono acidic basis, diia acidic bases and triac acidic basis. Depending on acidity, mono acidic, diasidic and triacidic. Can you repeat with me? Mono di and tri mono acidic bases. Mono acidic bases, diacetic bases, and triacidic bases.

[00:21:31]Repeat with me. Mono acidic bases. Di acidic bases, triacidic bases. So first part we are going to talk about depending on strength. So those bases that ionize completely ionize completely means release of O minus complete.

[00:21:50]Understood that is in the solution and high concentration of O minus will be there in that that is called as what we strong basis. Besh what that is called as strong bases. What it is called as strong bases. Okay. So now sodium hydroxide potassium hydroxide they are strong bases because the metallic ion M that is exactly you see sodium ion and potassium ion is released. Hydroxy ion is released. Understood not. So sodium ion is separated. Potassium ion is separated and O minus will be released.

[00:22:33]It's not loss. It's breaking of the what do you call compound to release as Na plus and O minus. Hydroxil release.

[00:22:44]Understood what we are calling it as hydroxil release. Weak bases.

[00:22:50]Okay. Those bases that ionize partially and give less concentration of O minus like ammonium hydroxide, calcium hydroxide, can they be able to release all the hydrogen atoms? No. Hydroxil ions no. They will not be giving hydroxil ion. Understood or not? So complete O minus they are not giving. In acid also we saw now they are not giving complete H+ correct now. So they were called as what? Weak acids they were called as weak acids and here also weak bases are there. Understood weak bases. Hydraulic hydroxyil ion completely are strong bases. Very good everyone online children come on type and send me the answers. So now look here depending on concentration.

[00:23:43]What does depending on concentration means? He concerned when a high amount of a base present in a fixed amount of solution that's called as concentrated understood but less amount of base is present in fixed amount of solution. So that's called as dilute basis. So basis will be of how many types of two concentrated and diluted. Can anybody give me the example of concentrated and diluted?

[00:24:15]A simple example of concentrated and diluted. Who can give me online offline children? You can refer the quantity also.

[00:24:33]Very good. Potassium hydroxide is a strong base.

[00:24:38]Come on. Potassium hydroxide is a strong base. That's not a big deal. Another things sodium hydroxide is concentrated base.

[00:25:04]Are they talking about these type of concentration? Can we check one time please? Now look here. So I took two beers in one see 50 ml water in both.

[00:25:38]Okay.

[00:25:42]N AOH is 30 ml or we will take 10 ml and here N AOH is 5 ml.

[00:26:10]This is beaker number one and this is beaker number two. So according to you which one is concentrated?

[00:26:19]Understood? That means the amount of substance is most important. First beaker is concentrated because that same sodium hydroxide in one quantity is more and in one quantity is less. So that's what it is considered as concentrated because the amount of sodium hydroxide is more in beaker number one. So we can take this as 20 30 if I'm taking 30 ml then 100% is highly concentrated. I hope you might have understood in 50 ml of water both the beers were having 50 ml of water. Both the beers were having how much? 50 ml of water. But in one weaker 30 ml of base is there NaOH is there and one only 5 ml is there. So which one is diluted bit weaker second one and which one is acidic? Sorry concentrated first one. So that's the way to identify. Very good children. Very good. Super. So shall we go back? So concentrated and acidic you understood now. Now beta monobasic dibasic we studied in acid. Do you remember monobasic and diabasic tribasic but here it is called as mono acidic di acidic the name is just reversed now mono acidic and dacidic in acid just have a flashback because when we were studying acids when we were studying acid we had discussed bowl.

[00:28:06]What would we use there in acid? In acid we used monobasic acid. What we use?

[00:28:13]Monobasic acid. And when we were discussing about monobasic acid, we discussed that acid that contain only one replaceable hydrogen atom. How many? Only one replaceable hydrogen atom. That means the one which will release only one hydrogen ion. Understood? Or hydrononeium ion is called as monobasic acid. what it is called as bit monasic acid. Why? Because okay I know that because we know that it is going to release how many beta? Only one H+ ion.

[00:28:55]How many H+ ion? Only one. Now we are going to talk about bases. This is called as mono acidic.

[00:29:12]That was mono basic. This is mono acidic. Then can you tell me how much it should release hydroxy ion? One. As the name suggest it should release how many hydroxy ion? One. So that's called as mono acidic. That's called as what? Mono acidic. See look here. Mono acidic basis. a base that produce only one hydroxil ion on dissociation in water per molecule per molecule. So each molecule so that's called as what we mono acidic base acidity of a base is the number of hydroxil ion acidity of a base is the number of hydroxil ion that one molecule of that base gives on dissociation in water. It is the number of hydrogen ion. It is the number of hydrogen ion of an acid with which a molecule of that base react to generate salt. This is a very important reaction.

[00:30:14]Everybody please read this one and explain. Let's see who can explain me in a better way. Please children start doing it. Explain me in a better way.

[00:30:22]Amish can you explain this?

[00:30:26]What is the meaning? Dependent on acidity. What does this mean here?

[00:31:05]because of lack of time today I am keeping math class in evening online for you people I'm giving AP introduction okay AP introduction AP arithmetic progression introduction I'm giving again I will come here and give offline also okay today Tomorrow afternoon introduction will be there in evening and extra class will be there because revision we have to start for your exams half yearly exams. When your exams are starting Amish?

[00:31:34]13th of July. A half yearly September.

[00:31:41]Huh?

[00:31:44]6th September.

[00:31:49]We have very less time and we have to start more work. Okay. AP we have to start, coordinate geometry we have to start and similar angles we have to start. Three chapters slot it is there.

[00:32:03]What did I ask you here everybody? I gave time to explain. Can you explain this one now?

[00:32:11]Acidity of a base is the number of hydroxil ion. Hydroxil ion means O minus. That one molecule of that base gives on dissociation in water. Gives on dissociation in water. It is the number of hydrogen ion of an acid. It is the number of an hydrogen ion of an acid with which a molecule of that base react. Understood or not? So we will see this and try and understand how it is.

[00:32:47]Got it? Can you check this one out?

[00:32:51]So first we will talk about H C.

[00:32:56]It will release H2 plus CL minus.

[00:33:00]Understood?

[00:33:02]H plus CL minus.

[00:33:06]N A O H. This is called as monobasic.

[00:33:16]Monobasic. What it is considered as bit of monobasic?

[00:33:21]It is considered as what? Monobasic. Why is this considered monobasic? Because it will release one H+ to react with base.

[00:33:29]Understood? Now NaOH Na plus O minus this is called as mono acidic.

[00:33:44]Understood? That means the hydroxil release will want needs one H+.

[00:33:53]Are you understanding the statement? Na is Na + O minus. Na is Na plus O minus.

[00:34:04]So one only hydroxil ion released. So it is called as mono acidic. Why? Because this one hydroxile ion need one hydrogen ion. Understood? to make one water molecule and salt.

[00:34:26]Got it? How many water molecules it will make? One water molecule it is making.

[00:34:31]Correct? Now H+ O minus will make what water molecule and here NaCCl salt will be formed. NaCCl salt will be formed. So beta monobasic means I am ready to release one H+ to release. See a monobasic person is talking to me. That monobasic person is telling hey I am monobasic. You know why I'm monobasic?

[00:34:56]But because I'm giving one H+. Why I'm giving one H+?

[00:35:01]So that a a mono acidic person will come and release what one O minus to neutralize.

[00:35:11]Are you understanding? So this is the concept of mono acidic and monobasic.

[00:35:17]This is the concept of what beta mono acidic and mono basic. Mono acidic and monobasic. The concept of mono acidic and monobasic is like that. So here can you tell me this one?

[00:35:40]Is it monobasic or mono sorry dibasic or di acidic?

[00:35:46]>> Di acidic absolute because how much it is there? 2 H minus ion it will release.

[00:35:53]So when it is releasing 2 H minus ions it will be needing 2 H+.

[00:36:00]Understood? So when it is releasing 2 H minus it is needing 2 H+. That's the concept actually. See if I'm giving two you should also give two now then only it will neutralize understood so as it is giving 2 H+ if it is giving 2 H+ for what it is giving 2 H+ to combine with 2 H minus so if someone is giving understand this just for sake understand 2 H+ that means how much O minus I need 2 H 2 H minus why I want to make two water molecule. Is it clear?

[00:36:41]Huh? So this the one the acid which is releasing this is called as the acid which will release 2 H+ is called as >> dbasic.

[00:37:02]The base which will release 2 H minus This is coming from base. This is coming from acid. Can I take an acid? H2S04.

[00:37:21]Acid. What acid? I can take H2SO4. H2SO4 is having how many hydrogen releasing?

[00:37:29]Two. They are dibasic.

[00:37:32]H2SO4 is dibasic. and calcium hydroxide diacetic.

[00:37:41]Let's check this one out.

[00:37:46]H2S04 will release 2 H+.

[00:37:51]Understood? So this is acid and it is releasing how many? 2 H+. So it is called as dbasic.

[00:38:03]Since it is releasing 2 H+ for whom it is releasing for a base. It is waiting for a base. Now base C AO Hole twice will release 2 O minus for whom this base is waiting acid. So what it is called as di basic.

[00:38:35]Did you understood the concept very nicely? What is di acidic and di basic?

[00:38:40]And based on this beta very good those who are writing die acidic and dibasic the reaction is exactly coming for neutralization. Now did you understood?

[00:38:50]Now are we ready to understand the definition? because it was very important to know the definition. So in that definition what it is telling acidity of a base. What it is called as acidity of a base is the number of hydroxil ion that one molecule of that base gives on dissociation in water. It is the number of hydrogen ion of an acid. Number of hydrogen ion of an acid with which a molecule of that base react.

[00:39:20]Understood? So a base is waiting for acid. Base molecule is waiting for acid.

[00:39:26]Acid molecule is waiting for base. So acid will release H+. Base will release O minus. So only acid is called as mono basic acid. Base will be called as monacidic base. Mono means 1 H+ 1 O minus. Di basic acid will release how many H+? Two. Di acidic base will release how many O minus? Two. They will neutralize. I hope everybody understood this one. So can we check here? Di acidic bases Mg whole hold twice and calcium hydroxide how many O minus it will release? Two and they will add with two H+. Correct Nita?

[00:40:16]So basis change red litmus paper to blue. So in acid we have ABC concept was we learned in acid acid turn blue litmus paper red.

[00:40:34]Acid turn blue litmus paper red. This was the concept we have studied. Correct or wrong? Acid turned blue litmus paper red. Acid is turning blue litmas paper red. Do you remember this? Acid turn blue litmus paper red. Base turn red litmas paper blue.

[00:40:57]VRB is it turn correct?

[00:41:03]Red litmus paper blue. B turn red litmas paper blue. B R understood. base turn red litmus paper blue. Base is turning red litmus paper blue. Strong base ionize completely.

[00:41:21]Weak base partially ionized mean they will not release O minus completely. But weak bases are not going to release O minus completely. Very good Kavia. So now concentrated base have more base in fixed amount of solution. We know this acidity of a base depends on number of O minus it is giving. So monobasic diabasic tribasic this also concept we studied.

[00:41:50]Now triac acidic base tri acidic base please remember the name of triac acidic base.

[00:42:04]Okay.

[00:42:07]Now come on. Tri acidic base. Come on note down. Tri acidic base. We'll write the names of tri acidic base. Who and all are the triac acidic bases? Come on write this. Tri acidic bases. Aluminium hydroxide and then iron hydroxide. They are triacidic bases. Aluminium hydroxide and iron hydroxide are triacidic bases.

[00:42:32]Tri acidic bases aluminium hydroxide and iron hydroxide. How many basic content they are releasing? Beta three or two.

[00:42:43]Amish for how many chapters or test is there?

[00:42:51]>> Huh?

[00:42:54]one one chapter light process and uh >> and >> reflection and >> refraction refraction reflection we have finished already now >> lens we have to start so I'll plan to start first because acid basis and salt is not coming correct now for you acid basis salt is not Done.

[00:43:45]I hope you might have understood this one. So now preparation of bases try basic we have understood aluminium hydroxide and iron hydroxide. So aluminium hydroxide and iron hydroxide.

[00:43:56]Thank you Kavia. Aluminium hydroxide and iron hydroxide are triacidic bases because they have two hydroxy three hydroxy ion. Two hydroxy ion we have seen three hydroxy ion we have seen one hydroxy ion also releasing we have seen now we're going to talk about preparation of bases that's a very important point everybody take out your note and start writing about because preparation of base is most important from here we are going to do our work preparation of base beta preparation of base so how to prepare base calcium is a Metal when it react with water which is liquid calcium react with water it makes a base calcium hydroxide and hydrogen gases released that's a simple reaction understand so here metal like calcium potassium sodium react with water to form bases and you know in reactivity series calcium potassium sodium they are highly reactive understand or not? So they easily react with water to make base. They easily react with water to make base. I hope you might have understood.

[00:45:38]I hope you might have understood. So we learned one very important thing that whenever a metal react with water specifically a strong metal. What type of metal? A strong metal it will be definitely a strong metal here means the metal which is reactive here. The metal which is reactive. Strong hair means reactives reactive metals when they will be reacting with water it will be making what better base calcium hydroxide and potassium hydroxide. Calcium hydroxide is weak.

[00:46:09]Its degree of dissociation of O minus is slower in comp compared to that of potassium hydroxide in compared to that of what? Potassium hydroxide. By the action of water on metallic oxide.

[00:46:22]Metallic oxide. First we saw metals. Now we are seeing metallic oxide. Metallic oxide like sodium oxide and then calcium oxide. Again it will be sodium hydroxide and calcium hydroxide. What it is making? Sodium hydroxide and calcium hydroxide. Please kindly check. So first was reaction of water on metal. Reaction of boton on metal hydroxide. These are the two ways through which we can make bases. These are the two ways through which what we can make beta we can make bases. The ways through which we can make bases. One is metal reacting with water. Second one is reacting with water. Okay. Can you give me one more example which is not present here?

[00:47:21]See here two are present. Can you tell me the one which is not present? Here calcium is there. Potassium is there.

[00:47:29]Can you tell me another metal which can react here? Come. Can you show me the reaction please?

[00:47:35]Sodium we can take. Sodium example we can take.

[00:47:39]>> Copper that will be weak.

[00:47:47]We magnesium.

[00:47:54]We can take example for magnesium also because magnesium yes metal oxides are also known as empoteric.

[00:48:04]All the metal oxides are not empotic.

[00:48:10]You know what is the meaning of empoteric?

[00:48:19]See amphoteric means amphoteric means I'm having dual nature.

[00:48:25]If I am with acid I will act as base.

[00:48:29]If I am with base I will act as acid.

[00:48:33]Are you understanding? Who is amphoteric? Dual nature dual character.

[00:48:37]So if an amphoteric is present with a base, it will act as acid. But if an amputeric is present with an acid, it will act as base. I hope you might have understood. So those amputeric substances are those substances which are exactly reacting according to the situation. Like present with acid, it will act as base. Present with base, it will act as acid. I hope you might have understood. So now calcium when somebody talked about calcium calcium and it is going to react with water it is making calcium hydroxide. So one example also I asked you we can take example of sodium sodium reacting with water it will make sodium hydroxide and H2 gas will be released. What gas will be released? H2 gas will be released here. Sodium hydroxide, sodium oxide reacting with water, sodium hydroxide is again released. Understood? So, sodium hydroxide is released. These are the preparations. These are the preparatory sections. I hope everybody understood this. Shall we go back to the next part please?

[00:49:54]Today I will release you little early because evening also I'm going to conduct classes. Some students are having exams.

[00:50:02]I hope everybody understood. Very good.

[00:50:05]Some students are having exams in school. So 5 minutes before I will leave. Okay.

[00:50:16]Done till here.

[00:50:18]So now by double displacement how can we explain about it? Double displacement bases when react with aqua solution of salt. Here salt is needed. Understand or not? Now did you saw acid reacting with salt?

[00:50:41]Did you remember acid reacting with salt? It was giving another salt and another acid acid salt reaction.

[00:50:56]Why we should go that much far?

[00:51:02]We must know because again confusion will come. This is old in preparation of acid only. Huh?

[00:51:26]Can you check this?

[00:51:28]Read this out.

[00:51:32]Sodium chloride. What it is? What is sodium chloride? Salt reacting with what they are giving?

[00:51:41]>> Salt. Another acid. Understood? So this comes under preparation only. Double displacement. So double displacement of acids are also done. Double displacement of bases are also done. Amish remember this. Double displacement of acids are also done. Double displacement of bases are also done. Write the one example at least. Remember salt plus acid. It is giving another salt. Sodium hydrogen sulfate and hydrochloric acid. So when one acid react with a salt, it will give another acid another type of salt. Got it? So this comes under double displacement. This comes under double displacement. Like can you see sodium nitrate? See here sulfuric acid, nitric acid and sodium sulfate is obtained.

[00:52:32]This is exactly double displacement and it is done in both acid and base. It is done in both acid and base. An acid react with a salt to give another's acid and another salt. A base react with a salt to give another base and another salt. I hope you might have understood that comes under what umbrella double displacement reaction. Understood?

[00:53:00]Double displacement reaction. And double displacement reaction is possible for both acid and base. What it is the content is saying acid react with salt.

[00:53:10]It gives another acid another salt. Same way base react with salt to give another base and another salt.

[00:53:30]Now is it okay by double displacement base sorry base react with a salt it is giving another salt and another base but here double displacement can you see this al this is pp formation yes and beta this is pp got it precipitate arrow is down so arrow down means it is making precipitate arrow down here means what beta it is making precipitate did you got my point. So now here by oxygen on metals already we know lithium will be joining with oxygen it will make lithium oxide. Lithium oxide is basic in nature.

[00:54:10]Lithium oxide is basic in nature. Now sulfates please remember this one by addition of oxygen on metal sulfides.

[00:54:18]Metal sulfides means this is sodium zincate. No yes zinc oxide is obtained and sulfur dioxide gas is obtained. This is a reaction where zinc sulfide zinc sulfide react with oxygen. It is making a base that is zinc oxide. Zinc oxide base they are making. See zinc oxide alkaline non-al because soluble insoluble that section must be checked by decomposition of salt also we can make.

[00:54:55]Understood not by decomposition of salt also we can make. So in the above reaction SO2 is an essential product. In some reactions we are making like that decomposition of copper carbonate magnesium carbonate. So when magnesium carbonate and copper carbonate got decomposed broken with the help of heat they're doing undergoing what?

[00:55:17]Decomposition.

[00:55:19]What heating what they giving? Copper oxide and carbon dioxide. Magnesium oxide and carbon dioxide they are bases.

[00:55:28]They are bases. So decomposition reactions also decomposition reaction of salts.

[00:55:35]Copper carbonate magnesium carbonate they are what? Salt. Base reacting with salt.

[00:55:44]Another base another salt. After that metal reacting with oxygen they will make base. Next metal sulfide reacting with oxygen.

[00:55:56]Metal sulfide reacting with oxygen they will make base. Salt decomposition.

[00:56:02]Which type of salt decomposition?

[00:56:04]Copper carbonate and magnesium carbonate. They will be giving copper oxide and magnesium oxide. Understood?

[00:56:12]No. Heating metallic nitrate gives bases. Sorry. On heating metallic that's what I thought. on heating metallic nitrates nitrates gives bases. Can we check this one time? Nitrates generally they will not be giving but one time we will see thermal decomposition correct.

[00:56:31]Zinc nitrate zinc oxide and nitrogen dioxide and oxygen release is there. Then calcium nitrate calcium oxide nitrogen dioxide and oxygen is there. So that's what is decomposition formation. We'll talk about the next part properties of basis in next class.

[00:56:54]Okay.

[00:57:01]Triangle is representing heat.