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Please refer to answer given by forum expert for 19406
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Cheer up, don't get depressed. Success is very relative term. You are prepared to work hard, so you are bound to succeed. If you are getting admission in engineering college, do join. Work hard to get your degree in flying colours. For PG you can again think of IIT through entrance exam, alternatively MBA through CAT in good institute is another option open to you. Other good opportunities will also be available once you get your degree. Joining a college for B.Sc. and simultaneously preparing for JEE is another option you can try. Here you will not lose one precious year of life. If you are able to get the desired result well & good, otherwise after B.Sc. again try for PG programmes in IIT, IISc, etc. Talk to your father frankly about what you want to do. You have passed XII and have appeared for JEE means you must be having study material with you. So there is no need to join any class, practice a lot at home, others have already listed useful web sites from which you can get the desired help. Those who have joined classes can also help you.Here also you can get necessary help from experts. Driveout the depression and start action as per plan you select. Best wishes.
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NIT Trichy or Surathkal both are very good institutes, if you are getting admission do not hesitate to join.
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I do not think that for the formation of bond the orbitals should belong to differedt energy. Following examples will clear your doubt, I suppose This second approach is also called the Atomic Orbital Approach to Bonding. The basic premise of this theory is that bonds are formed when atoms get close enough so that atomic orbitals on the individual atoms will be able to overlap so that the three dimensional probability regions share a common volume. This effectively increases the probability of finding bonding electrons between the two atoms. It also effectively results in the lowering of the energy state of the molecular system making the molecule more stable as a result of the overlap. The greater the overlap, the greater is the strength of the bond. Pure Atomic Orbital Overlap The simplest of these bonds involve the overlap of two "s" orbitals as in the example when two Hydrogen atoms get close enough to bond. The "s" orbitals overlap to form a "sigma" bond between the two "s" orbitals. A second type of overlap is between two "p" orbitals to form a sigma bond between two "p" orbitals. An example is the p-p overlap between two Chlorine atoms. A third type of sigma overlap is the overlap between an "s" orbital and a "p" orbital such as when a Hydrogen atom's "s" orbital overlaps with a "p" orbital of another atom like a Chlorine atom. Still if you have any doubt please specify.
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Ulmann reaction Diphenyl amine may be prepared by Ulmann reaction ; this is carried out by refluxing acetanilide, potassium carbonate,bromobenzene and a little copper powder in nitrobenzene solution ( copper accelerates the reaction): Cu C6H5NHCOCH3 + C6H5Br + K2CO3 ® ( C6H5)2NH + CO2 + CH3COOK + KBr This is useful general method for preparation of substituted diphenyl amines. Similarly triphenyl amine can also be prepared. Diaryl ethers can also be prepared by Ulmann reaction; Cu C6H5Br + C6H5OH + KOH ® (C6H5)2O + KBr + H2O Ulmann biaryl synthesis Iodobenzene on heating with copper powder in a sealed tube gives biphenyl; 2 C6H5I + 2Cu ® C6H5C6H5 + 2CuI Aryl chlorides or bromides do not give this reaction unless there is a ?I group o- and/or p- to the halogen atom. The methyl ester of diphenic acid(biphenyl-2-2?-dicarboxylic acid) may be obtained by heating methyl o-iodobenzoate with copper powder. 2 IC6H4COOCH3 + Cu ® o-COOCH3C6H4C6H4COOCH3
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why is ethyl iodide more reactive than ethyl bromide and ethyl chloride and why does ethyl flouride donot exist Flourination of hydrocarbons with pure F2 gas occurs explosively. This is due to low bond energy of F2 molecule (150.6kJ mol-1) and partly due to strongly exothermic nature of one of the terminating step ( i.e., R . + F . ® RF ) . This step is so exothermic (447.7 6kJ mol-1) that the energy released is larger than that required to break a C-C bond ( 347.3 6kJ mol-1) , thereby resulting in fission of the molecule. However direct fluorination of hydrocarbons may be carried out successfully by diluting F2 with an inert gas such as nitrogen or argon. Alternatively, alkyl fluorides are more convinently prepared indirectly by heating suitable chloroalkanes with inorganic fluorides such as AsF3 , SbF3, CoF3 , AgF , Hg2F2, etc. 2 C2H5Cl + Hg2F2 ® 2 C2H5F + Hg2Cl2 This reaction is called Swarts reaction. ( so ethyl fluoride exists) Due to polar nature of carbon halogen bond alkyl halides undergo nucleophilic substitution reactions. Better the leaving group more facile is the nucleophilic substitution reaction. Among the halide ions, the order in which the leaving group departs follows the sequence I >Br > Cl > F. Thus the order of reactivity is iodo alkanes > bromoalkanes > chloroalkanes > fluoroalkanes. This is due to the polarity of carbon halogen bond. Obviously at the first site, it appears that greater the polarity of C-X bond, more reactive shouls be the haloalkane. Polarity of C-X bond in methyl halides decreases in the order CH3-Cl (1.94 D) > CH3-F (1.82 D) > CH3-Br ( 1.79 D) > CH3-I ( 1.64 D) Therefore, the reactivity of haloalkanes should also decrease in the same order. However, the actual order is : RI> RBr >RCl > RF. This can be explained in terms of bond dissociation energies of the C-X bond : 452( CH3-F), 351 (CH3Cl), 293 ( CH3Br) ,234 (CH3I) kJ mol ?1. Thus C-I has minimum bond dissociation energy while C-F has maximum. As the bond dissociation energy increases, the ease of breaking the C-X bond and the reactivity of the haloalkane decreases. Thus the actual order is : RI > RBr > RCl > RF.
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powess academy is going to launch on line test series, where we can get ranked amongst the participants so we can improve our further performance. its not yet started will be operating very soon.
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Please do not get confused. you have already appeared for the exam., cleared your XII also, so you must be having good study material with you. Go through the NCERT books once again to clear the concepts. Then you need to practice for mcq for which whatever books you have start attempting questions.Verify your answers from the book, think logically where your answer went wrong, because now you have to concentrate on avoiding negative marking. Bring this negative marking score to nil during chapterwise tests in all subjects. Then go for mock tests, again with the same aim of not losing the earned marks in negative marking. Tests are available here also. If you want to go for postal coaching think of Fitjee/Narayana. MTG's PCMB is also useful for various tests. Have confidence in your sincere efforts, work hard and you will definitely succeed. Get your doubts cleared from teachers. Best wishes.
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NCERT XII books in all three subjects will help. You already have good collection with you, your coaching institute will also provide good study material. So you can concentrate on studies starting with NCERT books. In addition if you want go for Arihant- Organic, inorganic, physical chemistry. Study guide of Morrison so that you can solve problems given at the end of each chapter and verify your answers from study guide. Organic chemistry Finar vol I is very useful as many questions are based on reactions. List of books will be unending from friends, seniors,etc. What is important is sincere efforts, quality time in study. Best wishes.
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In the sawhorse projection, the molecule is viewed from an angle. So, the C-C bond is drawn backward obliquely. In this drawing the left hand carbon is nearer and the right hand carbon is away from the viewer. The eclipsed groups are drawn parallel to each other on the same side of oblique line; the staggered groups are also drawn parallel to each other , but on the opposite sides of the oblique line. An eclipsed form gets converted into the staggered form when the carbon atom is rotated by a 1800 angle around C-C bond. A partially eclipsed form is generally drawn from a staggered or from an eclipsed form by rotating one of the carbons in C-C bond around it through any angle other than 60,120,180,240,300 & 3600. The simplest example of an optically active compound is 2-chlorobutane. You can see the conformations of butane from any book. Replace one of the hydrogen on the oblique line by chlorine and you will get the various conformations of 2-chlorobutane.
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Morrison & Boyd and also Finar are authentic texts for Organic chemistry. It will not be exageration to say all the other books are derived from these two. I have been using these since my student days (1969 when I joined pre degree todays equivalent to XI ) and still I go to them for any difficulty in Organic chemistry. I agree with you that it is little bit lengthy. But study topic wise along with its study guide, attempt questions given at the end of topic. And then you will find it interesting , you will love organic chemistry.You can skip the topics which are not included for jee .Topics in part one of the book are more relevent for you, so read them(understand) properly.The language is very simple as if teacher is talking to us.If you study it with questions given at the end then you will not have any difficulty in organic.
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You should prepare your own time table first considering how much time you are required to attend the coaching class and your regular college. Devote time for completing any assignments given in the class.For better understanding of the subject it is good to start with NCERT books. If you understand the subject properly less time is required for completing the assingments, makes you interested in class. While preparing the time table please reserve some time for exercise/outdoor games/entertainment also. Three hours of serious study is sufficient for beginer.First write down your present daily schedule and then you can fit in well all the things given above. Best wishes.
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You want to appear for IIT JEE is very good, so please don't say that you are unfortunate. Many students simply don't want to go for this exam, because it requires serious study.Have you thought of joining postal coaching? Narayana/ Fitjee are good, if you wish you can join any one of them.MTG's PCMB helps a lot in preparing for the exam. Start with NCERT books and have a clear idea about fundamentals in each subject. Then gradually you can go to other books like Arihant. Here on goiit you get good study material, and the expert advice too. Still your teachers will be able to help you as and when needed. Best wishes.
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Biotech if you get in any good college is enough for undergraduate level. You can study well for three years and prepare for entrance exams simultaneouly for PG admission in IIT's/ good institutes. Second choice should be food technology in good college.
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On boiling vapour pressure of water increases may be true but is not the correct explanation of assertion. Ethyl chloride on boiling with silver oxide suspended in water gives ethyl alcohol. Ag2O + H2O  AgOH C2H5Cl + AgOH C2H5OH + AgCl Heavy metal ions particularly silcer ions catalyse SN1 reactions, the mechanism involves a fast pre-equilibrium step( the silver ion has an empty orbital) R-X + Ag+ fast [R-X-Ag]+ slow R+ + AgX
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Gravimetric analysis in simple terms is analysis by weight. In volumetric analysis( which we refer as titrations) volume is measured, from which we calculate the strength of solution. For example, determining amount of chlorine in the given sample of water, first we will have to precipitate it with silvernitrate to get silver chloride, filter , wash , dry and finally weigh it.
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You shouls have fundamentals clear first. If fundamentals are clear solving problems or Mcq is no difficult.For mcq you can practice from wherever you get good questions. MTG's PCMB is very helpful in this regard as it gives questions from nearly all exams, so it gives good practice. Also it contains latest changes about the question paper pattern.
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Here also you get course material,daily questions, tests, solution of your difficulties from experts. So you can treat it as online tution.
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Why think of pay package/ companies right now? If you are getting admission in IIT for MSc join without hesitation. Study hard these years, by the time you finish the course many new avenues will open. Best wishes.
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If you get integreted MSc course in any good institute, it is always good to join. Study well during these years and you have bright future. Fundamental sciences always have bright future. So don't think you have lost; join the course of your choice and do well in life. Best wishes.
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