AAU CET 2026 Chemical Bonding Entire Chapter with all concepts in 33 mins

[00:00:02]First of all guys, sincere apologies because next week screen towards the end. And last question.

[00:01:19]So what is the chemical bond actually is? Okay. So electroent coalent chemicals.

[00:02:21]>> [clears throat] >> For example, Atomic number three. 1 S2 2 S1 is 2 S2 Bon 2 S2 P1.

[00:02:56]So basically through the transfer of electronic configuration becomes 2.8 which is basically the configuration of neon a noble gas there is one more added over here so it becomes 2.8.8 8 and 2 8 is 10. 10 + 8 is 18. 18 is the configuration of argon element configuration that is basically the oct.

[00:04:08]So what are the limitations?

[00:04:11]What are the limitations of octed rule?

[00:04:14]Firstly, For example, L B H2 B2 B E H2.

[00:04:32]So they have much less than eight but BH2 exist.

[00:04:36]Then odd number of electron species 7 + 8 15 electrons NO2 7 + 16 right 7 + 16 23 electrons then certain times you will get much more than eight valence electrons for example PF5 that means Means phosphorus is bound to five florine atoms. So if you come count one two electron is shared four electron is shared six electron is shared eight electron is shared and 10 electron is shared da electron shares more than eight sf6 share correct. So these are the ones which have got more number of valence electrons more than the number eight [clears throat] the octed rule is you know violated here. All right then noble gas forms compound with florine forms compounds with oxygen. So these are the compounds which they form within and oxygen. So these are also available in the market. Okay.

[00:06:04]Market.

[00:06:09]So this is what it is guys. Okay.

[00:06:12]Most important from your competitive exam point of view parameters.

[00:06:19]parameters bond length.

[00:06:31]Next is your bond order.

[00:06:36]Next is your bond enthalpy or bond energy.

[00:06:41]And another one is bond angle.

[00:06:44]Generally radius ultimately if A is an atom B is an atom and the distance between the nucleus of both the is the bond length.

[00:07:10]Simple H2 oxygen oxygen will be two and nitrogen nitrogen will be three because nitrogen nitrogen in a nitrogen molecule three bonds are formed between two nitrogen atoms are born That is the energy required to break one mole of bonds. One mole is the important word.

[00:07:52]Okay. One mole of bonds that is basically the bond enthalpy or bond energy.

[00:08:02]elect for example if I take CH4 CH4 then these are bond angle this comes out to be 10 9.5 Okay.

[00:08:30]So these are the parameters. Now very very important is the relation between them. Remember bond order is directly proportional to bond energy. Definitely inverse relation.

[00:08:53]Single bond distance.

[00:08:57]All right.

[00:09:11]based on electro negativity. Electro negativity phone call f these are the most electrogative elements of the periodic table and electrogative they can share they can attract the share pair of electrons towards itself.

[00:09:35]These are the electrons that they are sharing. If B is more electrogative than A that means these two electrons will be pulled towards B side because B is more electrogative right moment dipole moment electro negativity difference so the dipole moment value will be non zero most electrogative element will pull it towards itself. So this is the dip moment vector mtor then oxygen is second most electrogative okay and lone pair. So dip moment vector from hydrogen will be in this direction.

[00:10:52]So here the dipole moment is present. It is a nonzero dip moment. That means a polar molecule. Okay. On the other hand, carbon dioxide is more vector equal and opposite direction.

[00:11:10]These will cancel out. So dip m comes out to be zero. That's why we consider it to be a nonpolar.

[00:11:17]I hope next is the most important thing that is known as VR.

[00:11:37]theory.

[00:11:40]Valention theory model shapes molecules or geometric shapes to model will repel each other. Okay. Order of repulsion. Order of repulsion.

[00:12:09]Order of repulsion that is basically loone pair repulsion is more than pair repulsion and it is more than bond pair bond pair repulsion.

[00:12:33]Number of bonding pairs. Number of pairs of elect.

[00:13:00]So the number of bonding pairs number of loan pairs zero arrangement to electrment A and B. Okay. Then this shape is known as linear. Example B E F2 number of bond pairs number of loone pairs then it is A3 type it is like this A B and BL shape shape trional planer shape.

[00:13:58]Example, BF3 BF3 number of pairs.

[00:14:18]Okay, this changes the shape example.

[00:14:32]Okay guys, next number of bond pairs A, B, B, B and B. This is known as very popular tetraadral.

[00:15:06]CH4 changes to pyramidal guys. pyramidal.

[00:15:25]Very very typical example of ammonia NH3.

[00:15:35]Next two both important both famous bond pair pairs. There will be how many loan pairs guys? Two loan pairs. Then the shape against it is known as band with one pair with two pairs and example. If you see water hydrogen oxygen pair.

[00:16:40]Okay. Next, next. Next, next. The five bond pairs, zero lone pairs. It is also very typical standard diagram. A B five, three over here and two over here.

[00:16:53]This becomes trional by pyramidal. Trional by pyramidal. Okay. Typical example is PCL5.

[00:17:06]PCL5.

[00:17:16][clears throat] Now the change of the shape.

[00:17:33]This is what? This is a seesaw.

[00:17:36]Seesaw SF4ine.

[00:17:42]Florine. Florine. Florine.

[00:17:47]>> [snorts] >> This is known as shape.

[00:18:14]For example, chlorine.

[00:18:18]Okay.

[00:18:34]Six bond pair, zero loan pair. Then it is the most famous guys. Okay.

[00:18:51]Very famous SF6 sulfur. Florine.

[00:18:54]Florine. Florine. Florine.

[00:19:18]This is known as square pyramid.

[00:19:21]Square pyram.

[00:19:23]Okay. For example, Br5 broine Bone.

[00:19:48]This is a square planer, guys.

[00:19:54]example xen okay because no gas family right so this is the most important topic guys which is known as which is known as the VAPR theory okay now a small topic for you known as the fazans rule then size or size or size then% no bond in the universe is purely coalent or purely ionic. Always remember guys, always so Then Na plus Mg + 2 Al + 3 + 3 is more.

[00:21:26]So this is how it is. All right. Moving on to the second last theory of this chapter that is the VVT. We are going to end chemical bonding very soon. So VBT VT valence bond theory guys. It discusses about the bond formation and overlapping of [snorts] P is dumb shaped. This is pi bond. Okay.

[00:22:08]Based on this we talk about a topic that is hybridization where this will combine.

[00:22:23]SP SP2 combine SP3 that means 50%.

[00:22:40]One out of three out of three that is 33.3%.

[00:22:48]Then 1 out of four that means 25%.

[00:22:54]Similarly, SP32 plusone pair 2 sigma 4 sigma 5 sigma 6 sigma. Oh my god. S P D2 S.

[00:23:27]Yes, this is also SP32. 1 sigma 2 sigma 3 sigma 4 sigma 5 sigma 5 sigma plus one lone pair. One lone pair again become six.

[00:23:47]Pya AT sp3D is the hybridization.

[00:23:51]So in this manner you can find out the hybridization of almost every atom every molecule sorry every molecule. Okay.

[00:24:00]Lastly ending the topic with molecular theory. Okay.

[00:24:23]Bonding molecular orbital orbital bonding molecular depending on and okay 14 electrons up to 14 [clears throat] equal up to 14 then comes bonding sigma star is anti-bonding okay then come sigma 2s 2s pi 2 px px py p atomic structure equally 2 p y pi 2p P Yigp 2px which is equal to pi* 2p y and then finally sigma star 2p z. If the number of electron is more than 14, if it is more than 14, then the difference is created here.

[00:26:09]A sigma 2p sigma 1 s then comes sigma* 1 s then comes sigma 2s then come sigma* 2s 2pz 2px =<unk> 2p y 2px is equal to p<unk> star 2py Okay. And it is less than sigma star 2p difference to create electrons in bonding minus number of electrons in antib-bonding 14 elect 12 electron 11 elect 15 elect 16 electron 17 electron 18 electron electron Number 14.5 0.5 0.5 2.5 Wow, sir. Wow. Wow. Wow. Directly. Yes.

[00:28:17]Nitrogen N2.

[00:28:33]N2 N2US N2 N2US 14 elect 2.5 O2 O2 electron Wow.

[00:29:34]14.5 this is how much this is another 1.5 this is another that means one.5gen inversely proportional to bond order Condeng will be minimum. So bondgen O2 less than O2 minus less than O22 minus. Wow sir last important topic that is hydrogen bonding hydrogen with most electrogative element most electrogative element gold medal silver metal bronze medal florine oxygen nitrogen phone hydrogen Intermolecular age bonding between two molecules intermolecular. For example, H2O panle is attached with a very electrogative element oxygen. You can take HF also hydrogen is attached with the most electrogative florine. You can take N3 also hydrogen is attached with the third bronze metal right between the molecule between the molecule or nitrofenol.

[00:31:33]Phenol is basically O and orthoposition of nitro N O2.

[00:31:41]Okay. So here also hydrogen can form bond within the molecule. Sole within the molecule typical example pq.

[00:31:55]So guys with this we are done with chemical bonding entire theory. Chemical bonding theory is done. Okay, it's done.

[00:32:04]Tomorrow I'll be coming with a hell lot of questions, guys.

[00:32:22]This is my commitment to you. Okay, I'm very sorry but this YouTube channel is dedicated for free content only and best quality free content. I hope thank you guys all the very best.

[00:32:49]signing off.

[00:32:55]Okay, guys. I I hope you see the video using your earphone. Okay, thank you.