Haloalkanes and Haloarenes Class 12 | Chemistry | Chapter 10 | CBSE NEET JEE | Part -1

0:00 hey all welcome to homeschool hope everybody are doing good and I have come up with class 12 chemistry syllabus as many of the students requested me to start with hello alans and hello arines here I am with the chapter hello alkanes and Hines see this is one of the most important chapters of Class 12 chemistry because if you can clearly understand the concepts of this chapter rest of the chapters in organic chemistry will become more easy okay so try to understand every Concept in a proper way fine and the concepts that I teach in this channel is purely based on ncer textbook because the neat examination or

0:47 the J Examination for that matter any entrance examination in any state majorly designed based on ncrt textbook so I will be teaching you the concepts from ncrt textbook in a proper way and here and there I will come up with ncrt textbook examples also because solving textbook questions is very very important for any competitive examination and more important for board examination clear and all the aspects that I cover in the video mainly focuses on the competitive examination so whichever the topic that is is more important for competitive exam that I

1:32 will go in depth okay so please follow all the videos for maximum benefit definitely this will help you out to sharpen your concept Clarity concept knowledge where that is the most important element that you should have to crack any competitive examination clear so let me start with the chapter hello alkanes and hello AR so we know what do we mean by alkanes right they are saturated hydrocarbons are called alkanes in an alkan if I replace one hydrogen atom by hogen atom then it

2:20 becomes hallo Alan suppose I have alkan methane so CH4 is methane so I will remove one hydrogen and I will add one hogen so it's a very basic knowledge that X in the sense it can be any hogen atom right it can be chlorine it can be Florine bromine or iodine whatever it is okay so I remove one hydrogen and I am adding one hallogen so what this gets converted into to it becomes ch3 and a fourth bond is with X okay so here what

3:07 you have observed is I am replacing right so we have replaced hydrogen atoms with halogens so such compounds are called haloalkanes clear so hallo alkanes are generally representated with the formula RX so RX is General formula this is general formula of hallo alkanes hallo alkanes so where R is nothing but any organic group it can be simple group like methy group or it can be C2 H5 group or it can be any complex organic group right so this is what the

3:56 general formula that we use to represent hallo alenes and now what do we mean by hallo arines suppose this is our Benzene right so you have one hydrogen atom at every carbon I will replace any one of the hydrogen atom with X then it becomes hallo arene aren in the sense aromatic compound the best aromatic and the simple aromatic compound we have is Benzene so if I can replace one hydrogen atom with any hogen then I can call it as haloarene clear and this is the general

4:43 formula for hallo arines and one more thing hallo alkanes can also be called as alky halides alky halides this is the general name common name for Halo alkanes whereas haloarenes are commonly called as arile halides arile halides okay so these are the common names that we most of the times use okay so this is our general introduction about hallo alkanes and Hallo arines and now let us understand everything about classification of hallo alkanes see majorly hallo alkan are

5:31 classified based on two factors the first one is based on the number of X atoms present in a molecule okay definitely Halo alkanes have X atoms hogen atoms So based on how many X atoms we have in a molecule uh we can classify hallo alkanes into different categories and another concept is based on this is very very important to understand based on the type of type of hybridization hybridization to which to

6:17 which X atom is attached that is hogen atom is attached okay so hogen atom is always attached to a particular carbon right so to what typee of carbon the hogen is attached is it attached to SP2 hybridized carbon or is it attached to sp3 hybridized carbon you know this way based on this concept also we can classify haloalkanes okay so these are the two themes on which hallo alkanes can be classified coming to the first category that is based on number of X atoms so depending on the number of X atoms hallo alkanes can be classified

7:02 into three varieties first one is monoo ales monohalo compounds okay second one is dialo compounds and third one polyal compounds so the name itself tells you everything what do you mean by monohalo compounds the compounds that has got only one hogen atom suppose you look at these examples ch3 CL right another example ch3 ch2 CL look over here in these compound hogen atom is only one so such compounds where you have only one

7:49 hogen atoms are called as monohalo compound coming to Diallo compound the name itself says you in these compounds there are two hogen atoms present it can be a same hogen atom or it can be a different hogen atom doesn't matter but in a single molecule if you have two hogen atoms then we call it as Diallo compounds and most importantly dialo compounds are again classified into two varieties one is gal gal dihalides this is very very important to understand carefully listen to this and

8:36 the other one is vinal vinal dihalides so let me first give you an example for gal dihalides look over here ch3 CH cl cl ch3 if you look at this compound the compound has got two hogen atoms here actually both are same both are chlorine atoms but both are attached to same carbon okay if two hallogen atoms are present on same carbon if two hogen atoms are present on same carbon then it is called as Gamal dihalides

9:21 but if the two hogen atoms are present on different carbon look over here look at this example even in this example you have two hogen atoms but they are on adjacent carbon atoms the two hogen atoms are present on adjacent adjacent carbon atoms that means side to side okay so such halides dihalides are called as vinal dihalides vinal in the sense adjacent carbon atom gal in the sense both of them are present at a single carbon so this is the difference between gal and vinal very very important to understand coming

10:08 to polyal compound nothing much to discuss here the name itself says if you have more than two hogen atoms suppose look over here CH cl ch2 cl okay so three hogen atoms are there in a single compound so more than than two hogen atoms if you find in a compound they are called as polyal compounds so this is a very simple classification that we have studied based on the number of hallogen atoms or X atoms now let us go for classification based on this particular theme so on what basis classification we have now it

10:53 is based on the type of hybridization of carbonat to which halogens are attached okay so here again we can have two categories here so based on this particular concept or theme we have two types one is uh hallo alkanes in which you know X is attached to where X is attached to sp3 hybridized carbon sp3 hybridized carbon carbon and the other one is X attached to SP2 hybridized carbon I'm not just writing a long sentence here

11:38 just wrote it in a shortcut way okay so what are the two varieties under this particular concept the variety where X is attached to sp3 hybridized carbon and the other classification is where X is attached to SP2 hybridized carbon okay now let us see what all the types that come under this category see under this category you will have primary haloalkanes secondary haloalkanes and tertiary hallo alkanes so hope you all are very well aware of the term primary compound secondary tertiary right

12:24 primary hallo alkane in the sense X is attached to primary carbon see if you don't have idea on primary secondary and tertiary carbon you know I have covered this aspect in 11th chemistry the chapter basic principles of organic chemistry uh the playlist link is provided in the description you can just go and check it out okay see to understand Class 12 organic chemistry chapters class 11 organic chemistry you should know that is basic without that you cannot understand Class 12 organic chemistry okay so before you start these videos I will recommend you to watch all videos of basic principles of organic

13:11 chemistry video links that is playlist link is provided in the description don't forget clear okay so what did I tell you if x is attached to primary carbon for example look over here ch3 ch2 CL okay see this carbon is called primary carbon so primary carbon is that carbon which has got only one CC Bond around okay so if if a carbon has one bond with other carbon around then it is primary carbon if hogen is attached to primary carbon then it is called primary hallo Alan okay if x is attached to secondary

13:56 carbon look at this example so the carbon on which I have put a star Mark no this is a secondary carbon because it has got two CC bonds around one is this side the other one is that side to such a carbon you have hogen attached and what is the hybridization of all these carbons it's sp3 right so what is the hybridization of this carbon sp3 because it has all single bonds around hybridization of this carbon this carbon also has sp3 okay so X is attached to sp3 carbon but that sp3 carbon is a secondary carbon here so such a hallo alkane is called secondary hallo alanes similarly tertiary in the sense

14:41 what tertiary carbon so this is tertiary carbon to tertiary carbon if hogen is attached then it is called as tertiary alkal halide or tary hallo alkan clear so this is uh the different types under this particular heading and you have two more important types okay that is Aly hallo alenes alile Group which is very very important group alile group in the sense look over here ch2 double bond ch2 so the hybridization of these carbons is SP2 SP2 right to this SP2 carbon if there is sp3 carbon like ch2

15:29 so now this carbon's hybridization is sp3 to this if hogen is attached then it is called as alile alile group so alile haloalkane it is okay see hogen is attached to sp3 carbon that sp3 carbon is in turn attached to unsaturated carbons so this is unsaturated group to this unsaturated group there is a carbon but that carbon is saturated because it has all single bonds around it has got sp3 hybridization to that carbon if x is attached then it is called alile hallo Alan okay so very very important idea

16:14 that you should have so here X is not directly attached to SP2 carbon or unsaturated carbon in between who is there saturated carbon is there okay so that is called alile halide similarly we have benzy halide benile halide in the sense same thing see this is Benzene we know in Benzene all carbons have SP2 hybridization so ch2 X look over here X is not directly attached to Benzene but in in between who is there ch2 group is there and that carbon is sp3 hybridized isn't it so this carbon is sp3 hybridized so this compound is called called as benile benile group it is so

17:03 this meaning is very very important so all these varieties come under this category which is that category in all these categories look over here x is directly attached to sp3 hybridized carbon okay and coming to the category where X is attached to SP2 hybridized carbon so here you have two varieties one is venile halide venile look over this example ch2 double bond CH X so here x is directly attached to unsaturated carbon which has got SP2 hybridization you should clearly know the difference between alile and venile

17:50 guys this is very very important in alile also you have ch2 double bond ch2 group that is unsaturated carbons are there but X is not directly attached to those carbon in between there is a saturated carbon to that X is attached but here directly X is attached to unsaturated carbon so that is the difference between alile and venile clear similarly you have arile arile halides that means on Benzine directly if you have X atom okay again you should know the difference between benile and arile in case of benile X is attached to some saturated carbon that saturated

18:38 carbon is in turn directly attached to Benzene but in case of a x is directly attached to Benzene drink okay uh that is to a carbon which has got SP2 hybridization so this is all about the classification of halal so similar classification you will have for alcohols also in the next chapter where instead of cl cl you know instead of hallogen we will put o so understanding this way in a flowchart form is much easier okay so try to take a screenshot or at least try to copy as it is in your book definitely if you can

19:24 learn like this you feel it more easy clear so this is all about classification of alkal halides so now let us talk something about nomenclature so for nomenclature uh you know you should really have some necessary basics for that also like you should refer the videos of 11th chemistry organic chemistry okay uh now I will select a few examples from your ncrt textbook and then I'll discuss those examples now if you look at these examples uh you know different varieties of compounds that I have written on a board let's try to discuss IUPAC names one by one so that all your rules whatever the rules that you already know will get

20:11 refreshed see whenever you have clbr iodine or any hallogen atom we consider that as a prefix that means its name we will write starting not at the end not as a suffix we should write it starting okay that is as a prefix clear uh look at this example ch3 ch2 CH CL ch3 so if something is mentioned in a bracket what does that mean that means that there is CL to this carbon not to this carbon it is to this carbon okay so this is your compound so how do you number it first you will have to number the carbon atoms in a chain right so if you number from left to right 1 2 3 4 so carbon having

20:58 hallogen atom gets number three but if you number from right to left 1 2 3 4 Carbon having hogen atom gets number two so what is our rule says you should number in such a way that hogen attached carbon or any substituent group attached carbon should have a least number so right to left is a correct way of numbering so now writing a name so the name of this hallogen is chloro right so this has attached to second carbon so we write it as two chloro two chloro then number of carbon atoms in a Chinese four so but all single bonds a so this is two chloro butane right coming to this example ch3

21:45 twice C in the sense there are three ch2 groups attached to this carbon so let me write elaborately so this is one ch3 group this is another ch3 group this is third ch3 group okay so this is our compound now you will have to number definitely look over here the hogen attached carbon should have a least number right so we give preference to this carbon this is one this is two and this is three right and now you have a substituent group CL and you also have two substituent group that is methy group so alphabetically C comes first so what I mention is one chloro 1 chloro hyphen 2 comma 2 2 comma 2

22:35 dimethy dile three carbon atoms are there so I can name it as propane coming to Third example so here what we should do is double bond containing carbon will have more preference than the BR containing carbon okay so we will start numbering from this side so this is number one this is two and this is three so how do we write the name it is three bromo three bromo okay prop prop and one in okay so this is how we will name and coming to this compound ch3cl its common name is chloro form sometimes for some of the molecule you should remember the common names also that's very very

23:20 important uh you know this is also called as alile bromide because look at this group this is alile group isn't it so this is alile bromide that's a common name so this is chloroform but IUPAC name this is only one uh carbon atom is there so meth and to that CL is attached so what we write is chloro methane one carbon all single Bond so chloro methane similarly we write this as dorom methane two chlorine atoms are attached to single carbon and you have only one carbon in a molecule so we write it as dorom methane and coming to this example all

24:08 these are from your ncrt book itself so look over here see first selecting aest Chine is very very important see if I go it in this zigzag pattern one 2 here nothing is there in the sense there is a carbon atom 1 2 3 4 5 so five carbons I can cover if I go it in this direction maximum number of carbons have to be covered right so that's the way we select longest chain and numbering how do you give numbering either from down to up or up to down it's always from up to down because double bonded carbon should have more preference so if I number from up to down this is one this is two this is three this is four and this is fine but if I number it from

24:55 bottom to up 1 2 3 double bonded carbon will have three position where if I go from Top double bonded carbon is having second position so minimum number you should have for double bonded carbon right so this is the correct way of numbering now writing a name so you have bromo at Fourth carbon right so we write it as four bromo four bromo then 1 2 3 4 5 five five carbon atom so pent 2 in so this is the name of that compound coming to this compound okay so here now double bonded carbons are this and this right so let me give number one for this this is two this is three and this

25:42 carbon is four okay so what I can write here is look over here you have two substituent groups here one is BR the other one is this ch3 okay alphabetically B comes first so what I write is three bromo uh two methy two methy okay so four carbon atoms in a chain so but one in okay so this is the way uh you have to follow to name hallo alenes so you have many more examples in your book so you can practice and if you have any doubt you can post your doubt in a comment

26:27 section e