TGPSC PCB EXAM PAPER 2 CHEMISTRY FREE VIDEO CLASS #tspsc #tgpsc #pcbexam #trendingvideo

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[00:00:01]Good morning friends. Today we are going to discuss PGPAC pollution control board two chemistry.

[00:00:11]Third lesson chemical bonding. Chemical bonding types of bonding overlapping of atomic sigma and pi bonds. Hydrogen bonding metallic bonding and vaspers theory right hybridization and so these all very important chemical bonding. Based on this some important questions and quick pre we can see. Okay. So don't miss this channel and you have to subscribe for more details and I will complete total syllabus up to July. So do follow my channel. Okay, we'll start the class. See first one all of you concentrate. First one is what I selected.

[00:01:12]Yes. You see this here?

[00:01:23]TGPSC right? TGPSC paper to chemist chemical bonding topic. Now topic is chemical bonding. Okay we are discussing now just 25 vsqs. 25 vsqs with best solutions. 25 vsqs with the best solution. These are important from this topic. Okay, we'll see now which bond is formed by transfer of electrons. Very important. Okay, so this is types of bond. Okay, so we know this here ionic bond is ionic bond is formed by the transfer of electron. We'll go for one example. See here example also there I will explain clearly. See ionic bond means your sodium I'm taking and chloride I'm taking. Sodium has your 11 electrons. 11 electrons. Whereas chlorine is 17 electrons. Okay. After losing of one electron is it become your 10 electrons. Okay. 10 electrons. So sodium is 10 electrons. 10 electrons.

[00:02:31]Similarly chloride chlorine adding one electron then become what? Cl minus. Cl minus in here it is 18 electron. 18 electron. See now what from sodium to chloride electron transfer taking place.

[00:02:48]Therefore by transferring of electron by transferring of electron ionic bond is formed. So therefore sodium chloride is formed by the transferring of electrons.

[00:02:58]Clear. This is the simple concept about here. Ionic bond is formed by the transferring of electron. So your answer is ionic bond. Next question you see which bond is formed by sharing of electron. Again same question here but sharing as they are transfering in sharing you know coalent bond is formed by the sharing of electron see I given here best example to understand is coalent bond what is coalent bond coent bond invol mutual sharing of electrons mutual sharing of electron between two atoms so that is homo or sometimes group example H2 molecule how it is formed here hydrogen and one more hydrogen These two hydrogens's are virtually sharing their electrons like this equal sharing and form here molecule. Clear sir. So like this we'll call here H2 molecule. We can write here H mod also we can write here H2 molecule. Clear? So like this here mutual sharing of electron coen bond is for clear that is your answer is colon bond. Next question you see overlapping of atomic orals leads to formation of overlapping area. Overlapping of atomic orital leads to formation of so here any atomic orbital overlap informed generally it is bond. So that is which one is chemical bonding. What is this chemical bond? That is not nucleus that is not ionization or that is not ions.

[00:04:32]Any overlapping is taking place that is called what? Chemical is called. So that is here. So overlapping is more effective. Overlapping is more effective. Overlapping means we have here SS overlapping, SP overlapping, PP overlapping, right? And PD overlapping like this here DD overlapping like so many overlapping are there. So this overlapping is more effective more effective. So between these two nucleus of atom and form your bond. So that is your chemical bonding. Clear. Next one.

[00:05:05]See add on add overlapping add on add overlaps forms. So here add on overlapping we get your sigma bond that is also called end on end overlapping end on end overlapping. What is this?

[00:05:22]For example you can take here this is sigma bond of p r overlap with the one more sigma. This is called here on ending. This will leads to form your sigma bond. Which one bond is sigma?

[00:05:38]Sigma bond is formed.

[00:05:41]Clear right? So that is your answer is sigma bond. Sigma bond. Next one. See fifth question is fifth question.

[00:05:49]Sidewise overlap leads to form. Sidewise means here you are taking same example like this. Here this is one pter. This is one more parchment and these two are overlap each other like this sidewise.

[00:06:04]This is called your sidewise overlapping or lateral lateral overlapping. Side wise or lateral overlapping. So this type of overlapping leads to form your what? This type of overlapping leads to form your what? Pi bond. Which bond is formed? Five bond is formed. Clear any doubt here? Yeah, that is it. So here first one is sigma bond.

[00:06:30]Second one is pi bond. Pi bond is formed. Okay. So that is your pi bond.

[00:06:36]Next one. See lat or lat. So we can see right. Next one. Sixth one. Which bond is stronger? Very important question.

[00:06:44]This is which bond is stronger. You tell me which one is strong end on ending making this.

[00:06:55]and uh sidewise or lateral overlapping.

[00:07:00]This is not a strong bond. This is weak bond clear. So this is weak bond.

[00:07:07]So pi bond is weak bond that is nothing but pi bond is weak bond and sigma bond is strong bond because end on end overlapping. So end on end overlapping will give you strong bond. Therefore, you can say which bond is strong bonding. Sigma bond is strong. Clear.

[00:07:27]Next one. We'll see. We'll see here.

[00:07:31]Uh hydrogen bond is strongest in is asking hydrogen bond also is strongest in. So which molecule hydrogen bond is strong? Actually what is hydrogen bond? Then take here hydrogen is form bond with the most electrogative elements like most electrogative elements like florine, oxygen and nitrogen. That's it. This electro negativity of florine is four, oxygen is 3.5 and nitrogen is three. So these three are these three are participating in hydrogen bonding. So these compounds we can see for first one is HF is formed hydrogen bond and H2O is formed water molecule hydrogen bonding and NH3 also form hydrogen bonding. See the option which is there. See that here option is HF is there and NH3 is there and HCL is there and PH3 is there. But in this these two these two are will form your hydrogen bond because nitrogen is there florine is there. But which is strong mean which is more electrogative.

[00:08:42]So which is more electrogative chlorine is more electrogative. Therefore this will form more than strongest bond.

[00:08:50]Clear? That is next one you see uh solution also given florine has electro negative just now and small size compared to leading strong. These two are clear. Next one. Metallic bond is due to that is very important. Metallic bond is due to it is formed here.

[00:09:12]Actually metallic bond is based on this VBT. VBT valence bond theory is also called C of electron theory.

[00:09:25]C of electron theory. What is C of electron theory?

[00:09:31]You can take here for example this is a water phone water pawn or see water and here we have a boat you can select a boat. So this boat is like a metal positive charge. This see water is nothing but electrons. So between these two there is a means relation attraction that is metal atom metal atom so many metal atoms surrounded by the sea of electrons. This is called your metallic bond. So so many metals are come close and release their electrons. This losing electrons are solid by the same metal. For example copper wire. Copper wire is used as a electrical conductor because on the surface of the copper wire so many electrons are present that is called your free electrons. Therefore it is a good conductor. It is a good conductor.

[00:10:34]It is a good conductor. Clear? So these electrons whenever we are applying voltage these electrons are helping move forward one terminal to another terminal. Therefore this type of bond is present in a metals. Therefore here see that is attraction between metal ions and its electron cloud that is called your C of electron theory. So sharing of electron is not possible. Transfer of electron not possible. Hydrogen are not there. But here attraction between metal ions and electron cloud. This is called metallic bond. Clear s that is your answer. Next one you know bond order bond order of O2 very very important I will explain clearly what is bond order how to find be careful so bond order can calculate by so many methods okay so now I will go for bond order this by logical manner logical logically I will be careful for example I want bond order of bond order is equal to bonding molecular ular orbital electrons minus anti-bonding molecular orbital antib-bonding anti-bonding molecular is anti-bonding molecular orbital electrons by two this is formula for bonded we need to use this one by taking O2.

[00:12:13]How to find O2 means oxygen. Oxygen oxygen here uh atomic number eight. How many oxygen are there? Two oxygen. Total number of electrons are 16. This is simple logic. If you know the 16, you will get the easy bond order. Oh, you can write here bond order is equal to 16. You can write as 16. You can write as 10 - 6 by 2. That's it. You get the answer. So what is the answer? So that is here 16 10 - 6. So that is nothing but 4 by 2 is equal to 2. That is nothing but between two oxygen atoms two bonds are present. This is called a border. Therefore it is it is mostly we know double bond. Oxygen contain which bond? Double bond. So we know this oxygen contain double bond. Therefore bond order is two. Bond order means number of bonds between two atoms.

[00:13:22]Number of bonds between two atoms are two. Therefore bond order is two. Your answer is two. Okay. If if you got here one more for example sometime they asking O2 minus then sir nothing will happen 18 actually it is total 16 minus means addition of electrons in the chemistry so it is 17 17 means okay 7 10 - 7 by 2 so that is nothing but what 3x2 3x2 3x2 means 1.5 is the border for example they are asking say they are asking O plus O2 + 2 somehat whatever it may be then whatever no problem here also you can take here plus means here rem of electron actually 16 16 - 2 you get here 14 14 means okay how can you write 10 - 4 by 2 so we'll get here 6 by 2 6 by 2 is equal to 3 so bond order is three like this we can find the bond order of any molecule okay we'll discuss future If same question will ask. Okay, that is a concept. Any doubt in this? Yes. Next we'll go for here. Higher bond order means very very important. Higher bond order means actually bond order means number of bonds. Bond order means number of bonds.

[00:14:45]Number of bonds between two atoms between two atoms are molecules. Two atoms are molecule in the molecule. So for example you can take here what is the what is the uh highest bond for example we'll go for one example I will give you one example to understand this concept all of you concentrate very important very important see here what is this I'm taking here carbon compounds C single bond C double bond C triple bond C then what I mean C single bond See bond order is bond order. Bond order is how many bonds are there? One.

[00:15:34]So bond order is one. How many bonds are there? B two. How many bonds? Three. So here we'll go for here. Here we need to take here I bond order means high border means we need to go for here bond energy. In this case bond energy actually bond energy of this one it required to break the bond here almost here uh 340 kiloj per mole energy required isn't it here for this one 16 kiloj per mole required here 827 kiloj per mole see what happen when number of bonds increases bond energy increases so which is strongest bond tell me which is strongest bond means this is strongest bond See now what is the question I bond order means what longer bond length no here bond length also we can write here bond length this is 1.54 anstrom units this is 1.34 anstrom units this is 1.21 21 anstrom unit limits say bond length is decreases bond energy increases and bond order is increases. So you can say bond order is directly proportional to bond energy and bond order is is inversely proportional to bond length see more the bond order lesser the bond length. Clear? So your answer is you can check it out here stronger bond stronger bond is higher the bond length higher the bond length means for example this is example more the bond order more the energy required that is more strong is the bond clear that is so greater the bond order means uh and stronger the attraction and shorter the bond length shorter the bond length clears any doubt in this right very now we'll go for Shape of shape of molecule. Which molecule it is? See this CH4 molecule?

[00:17:43]Methane molecule. So what is the shape of this molecule? We can go for here.

[00:17:47]Methane molecule. Methane. 1 2 3 four hydrogen's. We can keep it. Four hydrogen's.

[00:17:56]Right? Like this. We can give four hydrogen's. Now you can draw uh assume assume shape. You can keep the dots like this.

[00:18:07]Like this. Yeah, you can observe what happened here. You can observe it. This is one wall. This is second wall. This is third wall. This is fourth wall. You can pick it up here. Carbon. And I can means you can lift up. So how many words you can see? Four. Four means what? In chemistry. Four means tetra.

[00:18:30]Tetra. Hydra means one. Tetra. hydro tetrahydra. So where is the option tal?

[00:18:38]Yes, this is tetrad shape. So here when tetrad is there that ialization is sp3 bond angle is 90° 28 m that the common concept is discuss required in future right that is also so shape of b2 b2 b2 means berium chloride like this berium valence. So it is attached to two chlorides. Therefore see this is a linear shape 180° bond angle shape is linear linear molecule. So where is option you can see and hybridization is sp hybridization has linear linear shape and 180 bond. So your answer is linear is correct. Okay according to theme no lace no long shape change. Okay, see on this node lone pairs fif to find lone pairs lone pair electrons is equal to number of bonds how many bonds are there number of sigma bonds number of sigma bonds number of sigma bonds right minus a so you can take like this otherwise we'll go for one more small shortcut one more shortcut here you see so Group number group number group number group number minus number of bonds.

[00:20:10]Number of bonds. Right? You can see group number is berium atomic number four. You can subtract two from this.

[00:20:19]You get the group number. It is second group. So second group is two. Number of bonds are two. Two sigma bonds. one sigma two sigma 2 - 2 zero loone pairs so loone pairs are zero like this we can find the lone pair come here shape of NH3 is asking since say as it is NH3 like this we'll go for this here one lone pair is there on this central atom so this is pyramidal shape what is pyramidal shape so we can say trional pyramidal so according to whisper the we can go For this how to find the shape means see this actually nitrogen atomic number minus2 will get your fifth group. Fifth group means lone pairs we can find group number five number of bonds are 1 2 three bonds. So we can see three. So that is two. Two are electrons that is lone pair. So we can go for hybridization.

[00:21:19]Iization is equal to number of sigma bonds. Number of sigma bonds plus loan pairs. Number of sigma bonds are three. Lone pair is one that is four. Four means we can write 1 + 3. 1 means sbal. 3 means your p orbital. So 1 2 3. So this is s means 1. P means three. So is sp3. So when sp3 actually it is lone pair of electron. Due to lone pair of electron the shape is pyramidal.

[00:21:54]Render shift here. Bond ang 17° 48 minutes. Hybridization sp3. So that is about molecule. So 47 as well clearly. Next one shape of water molecule. Similarly according to visper theory it is bent molecule. So you can take your water molecule like this. This is water molecule. Right? It has two lone pair of electron. According to wher theory more repulsion more repulsion that is loan pair loan pair repulsion in the case of loan pair bond pair repulsion isn't it so according to square theory loan pair loan pair repulsion more than that of loan pair bond pair then bond pair bond pair so this is more therefore the bond angle is decreases from 7 to 104° 28 So this is a V shape or we can say bent shape. V shape it is bent or we can say reverse V shape also we can say angular shape angular angular shape of water molecule. Right here also hidation is sp3 right bondage is 184° 20 new minutes right and shape is V shape V shape.

[00:23:16]Don't forget this. Okay, that is about our concept.

[00:23:21]Next one respor based on very important is so it is based on just now what we discussing loan pairs. Loan pairs loan pairs.

[00:23:31]Therefore it is loan pair. Due to loan pair. Due to loan pair. Due to loan pair. Whatever we know. Due to loan pair it is affected by bond angles and shape of the molecule.

[00:23:49]Shape of the molecule. These two are affected by the log. Just now we discuss. You see in uh in BL2 no long.

[00:23:58]Therefore the shape is linear. Bond angle is 180. Vibration SP2 SP2 but in the case of ammonia it has one lone pair due to one lone pair repulsion is taking place due to repulsion bond angle is changed from actually original bond angle is 1 or 10° 28 minutes actually okay similar to methane methane but due to loan in methane no loan no loan pay in methane isn't it but in ammonia There is one role. Therefore, this board angling changes from 109 to 107°. You can see 107 that is due to ro and actually BK uh tetradal shape tetrad shape. But this shape is not tidal pyramid because of therefore due to lone pair due to lone pair it's bond angle and shape both are distorted. Similarly you can take the water molecule two lone pairs are there due to two lone pairs the shape also bend shape it is distortted from tetra 2 and bend shape is it shape and so bang angle actually it is also 9° 28 but it is distorted due to two loes repulsion become as a 4° so that is so here west theory base law means Lone pairs due to loone pairs what happening?

[00:25:29]Yes, what happening means bond angle and shape of the molecule will be distorted.

[00:25:34]That is a clear information. See this electron pair repulsions and see electron pair repulse the each and the minimize repulsions. Okay. based on the loan pair loan loan pair bond repulsions taking due to repulsion these two are effective that's next one which has maximum bond angle very important isn't it so we can go for here we can go for here uh NH3 just now we discussed NH3 right here uh NH37° 48 minutes bond angle right according to per and H2O just now we discussed 10 or 4° 28 minutes 28 minutes whereas methane no longer see 9° 28 minutes 28 minutes right in the case of CO2 CO2 is a linear molecule linear molecule due to linearity See hybridization is sp because only two sigma bonds two pi bonds are there. So sp means 180° bond angle. Therefore it has two bond angle compared to r. So this is 180 bond angle clear. So our answer is 02.

[00:27:06]Right. We'll go for here. Yeah, this is linear shape.

[00:27:11]Linear 180 means linear. That's it.

[00:27:15]Linear shape. Next, we'll go for hybridization of hybridization of C2 H2. This is becomes ethyine. C2 H2 means IUP name is ethine.

[00:27:33]Ethine. This is I up name and common name is common name is ethylene.

[00:27:42]This is common name. So both we consider right. So what is the hybridization?

[00:27:48]Simple in carbon chemistry. So we'll discuss 17 18 right together. Yeah. All of you concentrate together. We'll discuss. Okay. What is this? Actually in carbon compound carbon will give you only only uh three types of vibrations. One is DSP.

[00:28:15]Second one is SP2. Third one is SP2.

[00:28:19]That's it. Where SP? Where SP? SP2 SP3 is here SP is in all kinds.

[00:28:31]Here SP2 means key alps keys right.

[00:28:57]Okay. See what is the difference between this. Alkine means we have here CC triple bond. Alkan means double bond.

[00:29:09]Alkan means single bond. So all single bond compounds. For example, one compound is like this. It contain triple bond. One compound is like this. It contain double bond. One compound is like this. No single bond. No double bond or triple bond. Like this. You go for this whatever you see all of you see. So this carbon this carbon single bonded carbon therefore it is sp3 hybration. This carbon triple bond carbon sp this carbon triple bond attached carbon sp this carbon single bond attached carbon sp3. That's it. Clear? Now you can see this carbon this carbon. This carbon disc just this is sp3 this is double bonded sp2 here sp2 here sp3 simple 1 2 3 4 you tell me you tell me now whatever all are single bond so all four are sp3 carbons like this easily we can find now he's asking ethine ethine means C H2 double bond CH2 okay now tell me easily we can give the answer double bond carbon therefore this sp2 double bond carbon therefore sp2 now tell me what is answer your answer is sp2 is correct respect similarly we'll go for next question as it is you can give the answer what is the next question C2 H2 that is nothing but CH H cable bond CH see this is triple bond carbon therefore sp this is also cable one carbon sp your answer is sp this much easy hybridization of this okay so here it is sp2 means trional plane R trional plane R trional pl means 120° bond angle don't forget here SP means it is linear linear here. Okay.

[00:31:26]And bond angle is 180°. This is common concept for all. That is our information. Next we will see shape of shape associated with the SP2. Just know I see SP2 means SP2 means without loan P without loan P without loan PN plane and 120° B.

[00:31:52]So what is also see this is trional planer trional plan that's clear now we'll go for here shape with the sp means always without loar shape linear shape right and linear means always 180° so our answer is linear that's it next we'll go for which molecule is paramatic very important. So here mostly uh nitrogen diiamatic okay H2 diiamatic CO diamic only O2 is paramatic clear so O2 you know uh M molecular orital energy diagram you know anti-bonding anti-bonding anti-bonding here we can go for here 2 pi 2 pi and uh uh 1 minute.

[00:33:10]Yeah.

[00:33:13]Sigma 2px I 2p y 2p z are trans and bond but here in uh pi 2p y 1 electron pi 2pz 1 electron two unpad electrons are present in a anti-bonding in diagram therefore oxygen is paramatic okay because of two unpred electrons are okay I will explain full diagram When it required clear that is so remaining are not unparal next one molecular oral theory how to explain molecular orbital theory so it explain what first we'll go for molecular theory first thing see this is called your molecular orbital energy diagram here we have atomic orbitals, molecular orbitals and you can say here bonding molecular orital anti-bonding molecular or atoms, anti-bonding molecular art or like this here there are three types of these three or we can frame in a mid diagram. See we are taking like this G diagram. All of you concentrate what is G diagram. So this is called your atomic.

[00:34:48]Atomic order. This down one is down one is bonding molecular atom. Your upper one is anti-bonding molecular.

[00:35:02]This is this is energy. Energy order we are taking energy order energy order. Clear? Now based on this we can see by using molecular or diagram what we can explain. First point is first point is very important. First point is bond order.

[00:35:34]Second point is magnetic property.

[00:35:39]Magnetic property. That's it. These two are important. And third one also there electronic configuration. Electronic configuration of molecule.

[00:35:50]These three points are important. Okay.

[00:35:52]So we'll discuss one example and explain clearly. So first one you can see 22 question answer. So molecular theory explains so that is here bond bonding and magnetic properties clear. So M explain bond order stability magnetic property and electronic convolution also clear. So this is here energy order energy order also important energy order of this one means see which is least one B. So B M O is least energy then AO followed by A M O A M this is the energy order of R. Now bond order of N into N into N into N into N2 molecule. Just now we discussed bond order of N into nitrogen atomic number 7 7 + 7 14. So you can write here bond order is equal to 14 means how to write 10 - 4 by 2. So answer is 6 by 2 = 3. So your answer is three. This is the way. So don't go lengthy. Shortcut is yes. This is answer right. Clear. Now we'll go for which diatomic molecule has bond zero. See this here zero group elements. Mostly zero group elements do not contain any bond. Example we'll see.

[00:37:17]Here is giving H E2. This is not possible. That is H E bond. H E is not possible. H E H E bond is not possible.

[00:37:29]B because zero group elements do not pursue chemical bond. I will explain clearly how it is not possible. I'm taking here one H here right electronic confusion 1 S2 atomic number two. One more H atomic number two. 1 is 2 I'm taking here this oral energy this is here this is called linear combination of atomic or LC a LC a linear means 1 s2 1 s2 2 s2 2 s2 2 p2 to 2 p2 3 s2 3 s2 this is called linear combination I'm taking here 1 sle here see this diagram like this I frame diagram for you this 1 s2 orital of this helium. This is 1 s2 orbital of another helium. Right? Now this is atomic orbital. This is also atomic or this is just now discussed bonding molecular. This is anti-bonding molecular orbital. Now what happen you see now how many electrons here? Two electrons are how many electrons? Two electrons. Two electrons are filling here. Two electrons are that is atomic atoms we feel. Now this total electrons 2 + 2 how much? Four. This four we are filling according to according to ons rule least energy we need to above principle also will give you least energy first then pairing of electron.

[00:39:02]So four electron means first one second two. After filling of this we'll go for anti-bond four those this is the filling of our class by taking given electrons clear. Now how to find bond order? Bond order is equal to bonding molecular orbital electrons minus anti-bonding molecular orbital electrons by two. Now tell me how many electrons are bonding?

[00:39:32]Two electrons. How many electrons in anti-bonding? two electrons by two. So what do you get? 0 by 2. 0 by 2 means zero means no bond.

[00:39:43]No bond between helium to helium. This is the answer. So it is not possible.

[00:39:51]Therefore therefore therefore H E2 is not possible according to this theorem.

[00:40:02]Clear? So this is answer is H E2 remaining are positive remaining are positive. See this bonding electrons are two anti-bonding electrons are two. This is 22 two 22 two clear. So bond order is zero. See bond order zero. So here is does not exist.

[00:40:20]Clear? Any doubt? Yeah. So last one shortest bond length observed in just now I explained. So where shortest bond length means triple bond. See triple bond according to this I'm taking triple bond means carbon I'm selecting.

[00:40:36]Double bond means carbon and select single bond also carbon and select.

[00:40:41]Okay, this is strength. So he's asking shortest bond. So this is how many bond order is three. Bond order is two. This is bond order.

[00:40:53]Bond order. Bond order is one. Here bond length we are taking is asking length.

[00:40:59]Now bond length is asking. So I'm taking bond length. Bond length. All of you see this bond length. Okay. Bond length is here 1.21 21 anstrom units. Bond length here 1.34 angstrom units uh 1 54 anstrom units. Now tell me shortest volume single bond double bond bond bond not possible. So answer is double bond.

[00:41:33]So this is less value more border. So bond order inversely proportional to bond length.

[00:41:44]This is your importance of pollution control. So thank you friends.

[00:41:59]So YouTube search at the rate RGP RGP at the rate RGP 25.

[00:42:15]Okay, thank you very much.