Benzene molecular formula

Aromatic hydrocarbons are unsaturated cyclic compounds that are resistant to addition reactions. The aromatic hydrocarbons derive their name from the distinctive odors they exhibited when discovered. Benzene is the most important aromatic compound. Because many other aromatic compounds are derived from benzene, it can be considered the parent of other aromatic compounds. Benzene molecular formula is... 

The empirical formula of a compound represents the relative number of atoms of each type present in a molecule of the compound, whereas the molecular formula represents the actual number of atoms of each type present in a real molecule. For example, both acetylene (molecular formula C2H2) and benzene (molecular formula C5H5) have the same relative number of carbon and hydrogen atoms, and thus have the same empirical formula (CH). The molar mass of the compound must be determined before calculating the actual molecular formula. Since real molecules cannot contain frac-tionai parts of atoms, the molecular formula is always a whole-number multiple of the empirical formula. 

The most intriguing hydrocarbon of this molecular formula is named buUvalene, which is found in the mixture of products of the reaction given above. G. SchrOder (1963, 1964, 1967) synthesized it by a thermal dimerization presumably via diradicais of cyciooctatetraene and the photolytical cleavage of a benzene molecule from this dimer. The carbon-carbon bonds of buUvalene fluctuate extremely fast by thermal Cope rearrangements. 101/3 = 1,209,6(X) different combinations of the carbon atoms are possible. 

The classification of hydrocarbons as aliphatic or aromatic took place m the 1860s when It was already apparent that there was something special about benzene toluene and their derivatives Their molecular formulas (benzene is CgHg toluene is C7Hj ) indicate that like alkenes and alkynes they are unsaturated and should undergo addition reac tions Under conditions m which bromine for example reacts rapidly with alkenes and alkynes however benzene proved to be inert Benzene does react with Bi2 m the pres ence of iron(III) bromide as a catalyst but even then addition isn t observed Substitu tion occurs instead ... 

Reaction of benzaldehyde with 1 2 octanediol in benzene containing a small amount of p toluenesulfonic acid yields almost equal quantities of two products in a combined yield of 94% Both products have the molecular formula C15H22O2 Suggest reasonable structures for these products... 

Xylenes and ethylbenzene [100 1 -4J (EB) are Cg aromatic isomers having the molecular formula CgH g. The xylenes consist of three isomers o-xylene [954-7-6] (OX), xylene [108-38-3] (MX), and j -xylene [10642-3] (PX). These differ in the positions of the two methyl groups on the benzene ting. The molecular stmctures are shown below. 

Five double-bond equivalents can be recognised from the shift values (four for the benzene ring and one for the carbonyl group). The sixth double-bond equivalent implied by the molecular formula belongs to another ring, so that the following pieces can be drawn for the molecular jigsaw puzzle ... 

Preparation of Alkaloid III 100 g of the alkaloid mixture was dissolved in a liter of benzene and the resulting mixture filtered. The filtrate was diluted with approximately 4 liters of an aliphatic hydrocarbon solvent (Skellysolve 81 and the resulting mixture filtered. The filtrate was cooled with Dry Ice to cause precipitation, and the alkaloid removed by filtration. There was thus obtained an alkaloid, which, for convenience, is called Alkaloid III, having analytical values consistent with a molecular formula C32H4,05N, apparently an ester of a tertiary alkamine. 

Lauryl alcohol is obtained from the coconut and is an ingredient in many hair shampoos. Its empirical formula is C H. A solution of 5.00 g of lauryl alcohol in 100.0 g of benzene boils at 80.78°C Using Table 10.2, find the molecular formula of lauryl alcohol... 

Suppose that 10.0 g of an organic compound used as a component of mothballs is dissolved in 80.0 g of benzene. The freezing point of the solution is 1.20°C. (a) What is an approximate molar mass of the organic compound (b) An elemental analysis of that substance indicated that the empirical formula is C3H2C1. What is its molecular formula (c) Using the atomic molar masses from the periodic table, calculate a more accurate molar mass of the compound. 

Benzene and related aromatic compounds were hrst isolated from the gases given off during the heating of coal in the absence of air to produce a form of carbon known as coke, used in the manufacture of steel. That benzene had the molecular formula CgHg was determined in 1825, but it took over a hundred years to prove its structure even though its correct structure was suggested in 1865. 

During this period of time we, and a number of other research groups, have been investigating the reactions of highly halogenated aiynes and hetarynes with aromatic hydrocarbons, for the reasons outlined in the introduction. In a reaction of pentafluorophenylmagnesium chloride with ethylene oxide in the presence of benzene, it was shown that, as well as 3-pentafluorophenylethanol (23) a by-product of molecular formula C12H6F4 was produced 43>. 

Analysis and mass spectrometry showed it to have the molecular formula C HeBrFa. This could have been formed by the addition of magnesium bromide to tetrafluorobenzyne followed by the elimination of magnesium bromide-fluoride to give bromotrifluorobenzyne (30) and hence the compound (31). Analysis of the 19F n.m.r. spectrum and more particularly the preparation of (31) from o-bromotetrafluorophenyl-magnesium bromide and benzene confirmed the suggested mechanism. In this latter reaction the ratio of (31) to (24) was 99 1 54>. 

Common Name Benzene Synonym benzol, cyclohexatriene Chemical Name benzene CAS Registry No 71-43-2 Molecular Formula C6H6 Molecular Weight 78.112 Melting Point (°C) ... 

UV absorption maxima occur at 236, 274 and 316 nm. The molecular formula of zearalenone is C18H22Os, its molecular weight is 318.4 g/mol and its melting point is 162-163°C (Blackwell et al. 1985 Josephs et al. 2003). The maximum fluorescence in ethanol occurs with irradiation at 314 nm and with emission at 450 nm. Its solubility in water is about 0.002 g/100 ml. In an aqueous solution of inositol, the presence of zearalenone can change the crystal structure of this alcohol, which indicates the possibility of interaction between both substances (our observations). Moreover, zearalenone is slightly soluble in hexane and progressively more so in benzene, acetonitrile, methylene chloride, methanol, ethanol and acetone. However, it is readily soluble in aqueous alkali. 

Based on your molecular formula alone, you can make some decisions regarding the unknown labeled with a number. For example, there must be at least six carbons in order for it to have a benzene ring. If there is a benzene ring, chances are that it will have approximately the same number of hydrogens as carbons. If there is one oxygen, it is probably either an alcohol, ether, aldehyde, or ketone. 

Pseudopterosin X (1) was isolated as a yellow colored gum. The UV spectrum of 1 showed maximum absorption at 280 nm due to the presence of a highly substituted benzene chromophore [10], Its IR spectmm displayed intense absorption bands at 3,470 (OH), 2,904 (CH), 1,705 (C = O), 1,595 (C = C) and 1,100 (C-0) cm . The high-resolution electron-impact mass spectmm (HREIMS) of 1 showed M+ at m/z 474.2622, and this mass provided molecular formula indicating the presence of nine double bond equivalents in 1. The C-NMR chemical shift assignments of 1 are shown around stracture 1. On the basis of the detailed NMR studies and comparison with the reported pseudopterosins in the literature and L-xylose [3-5], stmcture 1 was proposed for this new natural product. 

The molecular formula of benzene is CeHe. Remember that each carbon atom must form a total of four bonds. A single bond counts as one bond, a double bond counts as two bonds, and a triple bond counts as three bonds. Hydrogen can form only one bond. Draw a possible structure for benzene. 

If you completed the Concept Check activity on page 12, you drew a possible structure for benzene. For many years, scientists could not determine the structure of benzene. From its molecular formula, CeHe, scientists reasoned that it should contain two double bonds and one triple bond, or even two triple bonds. Benzene, however, does not undergo the same reactions as other compounds with double or triple bonds. 

Kekule s other major contribution was his hypothesis, later shown to be correct in essentials though notin details, regarding the structure of the petroleum hydrocarbon known as benzene. This important chemical has the molecular formula CgHg, and it was Kekule who first recognized, in 1865, that the six carbon atoms link to each other to form a ring ... 

Aromatic hydrocarbons (or arenes) are a subset of the larger set of hydrocarbons and the simplest of these Is benzene. It is a colourless liquid and has a molecular formula of C H. The molecular formula shows that benzene Is deficient in hydrogen atoms and suggests that It Is an unsaturated hydrocarbon. 

Benzene was first isolated in 1825 from coal tar. Later, chemists determined that it had the molecular formula CgHg. Further investigation of its chemical behavior showed that benzene was unlike other hydrocarbons in both structure and reactivity. 

Benzene s molecular formula is C6H6, but it does not behave like hexane, hexene, or any of their isomers. One would expect it to be similar to these other six-carbon hydrocarbons in its properties. Table 4 provides a comparison between benzene, hexane and 1-hexene. The table shows that there are major differences between benzene and the straight-chain hydrocarbons of die same carbon content. Hexene s ignition temperature is very near to hexane s. The flash point difference is not great, however, there are significant differences in melting points. The explanation for these differences is structure which in the case of benzene is a cyclical form with alternating double bonds. 

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