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hall ticket download nhi honge, admit card 15 march tk aa jana chaeye
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A force is a push or a pull upon an object which results from its interaction with another object. Forces result from interactions! As discussed in some forces result from contact interactions (normal, frictional, tensional, and applied forces are examples of contact forces) and other forces are the result of action-at-a-distance interactions (gravitational, electrical, and magnetic forces). According to Newton, whenever objects A and B interact with each other, they exert forces upon each other. When you sit in your chair, your body exerts a downward force on the chair and the chair exerts an upward force on your body. There are two forces resulting from this interaction - a force on the chair and a force on your body. These two forces are called action and reaction forces and are the subject of Newton's third law of motion. Formally stated, Newton's third law is:  For every action, there is an equal and opposite reaction.
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CH3, only show R effect not +R or -R
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what is overleping and mirror image is overlap each other?
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The same is true when an alkene reacts with water in an addition reaction to form alcohol. The hydroxyl group (OH) bonds to the carbon that has the greater number of carbon-carbon bonds, while the hydrogen bonds to the carbon on the other end of the double bond, that has more carbon-hydrogen bonds.The chemical basis for Markovnikov's Rule is the formation of the most stable carbocation during the addition process. The addition of the hydrogen to one carbon atom in the alkene creates a positive charge on the other carbon, forming a carbocation intermediate. The more substituted the carbocation (the more bonds it has to carbon or to electron-donating substituents) the more stable it is, due to induction and hyperconjugation. The major product of the addition reaction will be the one formed from the more stable intermediate. Therefore, the major product of the addition of HX (where X is some atom more electronegative than H) to an alkene has the hydrogen atom in the less substituted position and X in the more substituted position. However, the other less substituted, less stable carbocation will still be formed to some degree, and will proceed to form the minor product with the opposite attachment of X.The rule may be summarized as "the rich get richer and the poor get poorer": a carbon rich in substituents will gain more substituents and the carbon with more hydrogens attached will get the hydrogen in many organic addition reactions.
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what is mean different in disteriomer and enantiomer
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when chiral carbon is preasent in compound and a meso compound or meso isomer is a non-optically active member of a set of stereoisomers, at least two of which are optically active. This means that despite containing two or more stereocenters (chiral centers) it is not chiral. A meso compound is superposable on its mirror image, and it does not produce a "(+)" or "(-)" reading when analyzed with a polarimeter.For example, there are 3 isomers of tartaric acid (depicted below), there is a meso compound (the 2R,3S and 2S,3R isomers are equivalent) and the optically active pair of levotartaric acid (D-(S,S)-(−)-tartaric acid) and dextrotartaric acid (L-(R,R)-(+)-tartaric acid). In the meso compound an internal plane of symmetry exists, bisecting the molecule which is not present in the non-meso compounds. That is, on rotating the meso compound by 180° on a plane perpendicular to the screen, the same stereochemistry is obtained, again this is not seen in the non-meso tartaric acid. It is a requirement for two of the stereocenters in a meso compound to have at least two substituents in common (though having this characteristic does not necessarily mean that the compound is meso). For example, in 2,4-pentanediol, both the second and fourth carbons, which are stereocenters, have all four substituents in common.Since a meso isomer has a superposable mirror image, a compound with a total of n stereocenters cannot have 2n stereoisomers if at least one of the stereoisomers is meso.
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C6H5-CH3-CH2-CH2-CH2-CHO is called phenyl Pentanal
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An olefin that has two double bonds
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ADMIT card of iit jee will be distributes after 15 march
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"Main Entry: connective tissueFunction: noun: a tissue of mesodermal origin that consists of various cells (as fibroblasts and macrophages) and interlacing protein fibers (as of collagen) embedded in a chiefly carbohydrate ground substance, that supports, ensheathes, and binds together other tissues, and that includes loose and dense forms (as adipose tissue, tendons, ligaments, and aponeuroses) and specialized forms (as cartilage and bone)" Merriam-Webster OnLine, www.m-w.com, my favourite dictionary.If you understand that... Ok, I don't know if blood is of mesodermal origin (mesoderm, again according to M-W online, is "the middle of the three primary germ layers of an embryo that is the source of many bodily tissues and structures (as bone, muscle, connective tissue, and dermis)"), but some other characteristics fit it well. It does consist of various cells (red blood cells, all sorts of white blood cells, thrombocytes), and an array of different proteins (though fibrins only form interlacing fibres during clotting, but this can be seen as a form of specialisation for transport - if there were protein fibres around in blood all the time, it could be pretty difficult for RBCs and other cellular stuff to move in it).
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first you use Sn/HCl and second NaNo2/HCl and third H+ nitrobenzene ----------->aromaticamine ---------->N2+Cl-(C6H5)--------> benzene
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sir how to identifiy that compound is planar or non planar
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you can try resonance kota on phone 07443012222,there are distributes mock test papers of 12th
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The classical term ortho effect was quantitatively analyzed and decomposed into its real or supposed components, using the acidity of eleven 2-substituted benzoic acids as a sample. The substituent effects were evaluated by calculations at the B3LYP/6-311+G(d,p) level by means of isodesmic reactions, separately for the acid molecules and for their anions. An intramolecular hydrogen bond, affecting the acidity moderately, was found only in the case of 2-methoxy- and 2-dimethylaminobenzoic acids. For the other acids, the often-employed interpretation invoking a hydrogen bond is wrong: the pertinent form was not revealed by calculations or by infrared spectroscopy. Another widespread explanation relying on the steric inhibition of resonance of the COOH group is also not correct in most cases: only some acid molecules are nonplanar (with substituents tert-Bu, CH2Cl, CF3, NO2, Cl) and the steric inhibition exists also in the anions, thus partly cancelling this effect. The main part of the ortho effect consists of polar effects (inductive and resonance) transmitted through the ring and of purely steric effects. Their tentative separation was based on comparison with the 4-substituted isomers. Polar effects are most important for the acidity and are not very different in the ortho and para positions (rough estimate 0.8:1). Steric effects are strong but mostly of similar magnitude in the acid as in the anion; hence they are of restricted importance for the acidity. They may be better described as van der Waals interactions rather than as short-range field effects. The whole analysis leads to the conclusion that the acidity of ortho-substituted benzoic acids cannot be interpreted by a simple universal theory.
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sir please explain what is electrophilic addition reaction?
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what is rule of +I effect
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History of Beawar City
Beawar is situated at a strategic location in Rajasthan, India. The city was founded in 1836 as a military cantt, at an important location between Jaipur, Jodhpur and Udaipur.
It was named after a local village called Beawar Khas. It meets all the requirement for becoming a district, sooner or later it is going to happen.
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sir, what is rule of identify geomatrical isomeres
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Vriti Edustore
