Octane molecular formula

The next six alkanes are named pentane, hexane, heptane, octane, nonane, and decane. Their molecular formulas are CjHij, C5H14, CjHjg, C Hjg and... 

CHEMICAL NAME = 8-Azabicyclo[3.2.1] octane-22carboxylic acid, 3-(benzoyloxy)-8-methyl-, methyl ester CAS NUMBER = 50-36-2 MOLECULAR FORMULA = C17H21N04 MOLAR MASS = 303.4 g/mol COMPOSITION = C(67.3°/o) H(7.0%)... 

A formula such as C4H9, which is determined from data about percent composition, is called an empirical formula because it tells only the ratios of atoms in a compound. The molecular formula, which tells the actual numbers of atoms in a molecule, can be either the same as the empirical formula or a multiple of it, such as C8H18. To determine the molecular formula, it s necessary to know the molecular mass of the substance. In the present instance, the molecular mass of our compound (a substance called octane) is 114.2 amu, which is a simple multiple of the empirical molecular mass for C4H9 (57.1 amu). 

Then multiply the subscripts in the empirical formula by this multiple to obtain the molecular formula. In our example, the molecular formula of octane is C(4x2)H(9x2)/ or CgH18. 

The next six alkanes are named pentane, hexane, heptane, octane, nonane, and decane. Their molecular formulas are C5HI2, C6H14, C7H16, CaHJg, CjH, and C10H22. The alkanes do not stop at the ten-carbon chain however. Since these first ten represent flammable gases and liquids and most of the derivatives of these... 

Isobutane, isopentane, and neopentane are common names or trivial names, meaning historical names arising from common usage. Common names cannot easily describe the larger, more complicated molecules having many isomers, however. The number of isomers for any molecular formula grows rapidly as the number of carbon atoms increases. For example, there are 5 structural isomers of hexane, 18 isomers of octane, and 75 isomers of decane We need a system of nomenclature that enables us to name complicated molecules without having to memorize hundreds of these historical common names. 

Octane and heptane are two ingredients of gasoline. Octane has 84.12% carbon and 15.88% hydrogen, and heptane has 83.90% carbon and 16.10% hydrogen. Their molecular masses are 114 amu and 100 amu, respectively. What are their molecular formulas ... 

Similarly, in Figure 6.4.4, the compound has the molecular formula CgHig and is one of the octane isomers. It is plainly not the straight chain octane, since the eight carbon atoms are not joined in a single chain. The longest chain is the one shaded - the two alternatives are given. Use a model kit if necessary to appreciate this structure. 

Professor Rufus T. Firefly of Fredonia State University wanted to stump his ace chemistry student. Sea Water (C-H2O, alias formaldehyde). The professor asked Sea Water to deduce the structure of menthol, the principal flavoring constituent of peppermint, on the basis of the following data the molecular formula of menthol is C10H20O when heated in the presence of sulfuric acid, a dehydration reaction ensues to form compound A ozonolysis of compound A followed by a reductive workup yields 3,7-dimethyl-6-oxo-octanal menthol also reacts with nitric acid and vanadium oxide, when heated, to form 2-isopropyl-5-methyl-hexanedioic acid. 

Octane is an eight-carbon alkane and has a boiling point of 125.6°C, a flash point of 56°F, a flammable range of 1.0 to 6.5%, and an ignition temperature of 428°F. The structure and molecular formula for pentane are shown in Figure 5.31. 

Compounds composed entirely of nonmetals are typically molecular substances that tend to be gases, liquids, or low-melting sohds at room temperature. Examples include the common hydrocarbons we use for fuel (methane, CH4 propane, C3H8 octane, CgHis) and the gases HCl, NH3, and H2S. Many pharmaceuticals are molecules composed of C, H, N, O, and other nonmetals. For example, the molecular formula for the drug Celebrex is C17H14F3N3O2S. 

Isobutane has the same molecular formula, C4HJ0, as w-butane, but a different structure. Molecules having the same molecular formula but different structures are called isomers. Isomers have different properties from each other and can be distinguished by inspecting their structural formulas. For alkanes, the number of possible isomers increases with the number of carbon atoms in the alkane. Pentane has 3 isomers, hexane has 5, octane has 18, and an alkane with 20 carbon atoms has 356,319. 

A condensed structural formula, or simply a condensed structure, shows the same information as a structural fonnula, but in a condensed form. For instance, the molecular formula, structural formula, and condensed structural formula of octane are as follows ... 

In molecules where the carbon atoms do not form a single, unbranched chain, branches are indicated using additional parentheses in the condensed structural formula. For example, 2-methylheptane has the same molecular formula (CgH,g) as octane. In effect, the chain is one C atom shorter than in octane and one of the hydrogen atoms on the second C atom has heen replaced by a methyl group. The molecular formula, structural formula, and condensed structural formula of 2-methylheptane are as follows ... 

A manufacturer of pure hydrocarbons offers for sale 18 different alkanes called OCTANES, whose molecular formula is CgHig. Seventeen of them are clear, colorless liquids at room temperature. The eighteenth is a white crystalline solid. We determine their boiling points, and find that they range from 99 to 126°C some of the boiling points are so close to others that they cannot easily be distinguished from each other. Now we try a somewhat more heroic experiment. We take 18 identical new automobiles with empty gasoline tanks and add one of... 

Clearly, what we have here are 18 different substances (tsOMERS) that are distinct in their properties despite their common molecular formula. As the number of C atoms in the alkane increases, the number of isomers increases sharply. This comes about because branching can become more extensive. We will illustrate this with one of the octanes ( isooctane ), which serves as the standard of 100-octane gasoline. Imagine that we construct a model of this molecule from atomic models by starting with methane, CH4, and adding C and H atoms with the provision that with each addition we maintain the proper covalencies for C and H. We remove one H, shown as H, and add Hg as shown ... 

The next six alkanes are named pentane, hexane, heptane, octane, nonane, and decane. Their molecular formulas are C Hjj, C H,4, CjH,. C H , CjHj, and CiqHjj. The alkanes do not stop at the ten-carbon chain however. Since these first ten represent flammable gases and liquids and most of the derivatives of these compounds comprise the vast majority of hazardous materials encountered, we have no need to go any further in the series. The general formula for the alkanes is C Hj ,.2. The letter n stands for the number of carbon atoms in the molecule. The nmnber of hydrogen atoms then becomes two more than twice the number of carbon atoms. Since there is more than one analogous series of hydrocarbons, you must remember that each series is unique the alkanes are defined as the analogous series of saturated hydrocarbons with the general formula C Hj +2. 

The molecular formula and the formation of octane from A and B indicate that both com-... 

After 300 transfers in the two-phase system iso-octane aqueous buffer pH 8.0 a new component of the hop alpha acids mixture named adhumulone was isolated in 1952 (43). It has exactly the same molecular formula as humulone and the specific optical rotation at the NaQ-line in methanol amounts to -187. The yellow oil can be obtained as a crystalline derivative upon reaction with 1,2-phenylenediamine (melting point 98°C). The spectrometric characteristics and the chemical properties are analogous to those of humulone (44). The only changes in the NMR spectrum relate to the protons in the acyl side chain. The new absorptions are a triplet (3H)... 

The light-brown oil with molecular formula of C22H32O0 and a specific optical rotation of -172 at the Nap-line in iso-octane, displays nearly identical spectrometric and chemical properties as humulone. In the H NMR spectrum the methine proton of the acyl side chain is shifted between 5 1 and 5 2, while an additional methylene function absorbs in this region also. Since the spectrometric changes did not allow unequivocal identification, chemical proofs have been worked out. In addition to the synthesis (see 2.4) prehumulone has been degraded in alkaline hydrogen peroxide (48). In the reaction mixture 4-methylpentanoic acid has been isolated corresponding to oxidative fission of the acyl side chain (49). It follows that prehumulone is (-)(6R)-4,6-bis(3-methylbut-2-enyl)-3,5,6-trihydroxy-2-(4-methylpentanoyl)cyclohexa-2,4-dienone (10, Fig. 12). 

The tetronic acid derivative is obtained as by-product upon boiling of humulone in an aqueous buffer pH 5.4. It is isolated as the band with K 0.35 by CCD distribution in the two-phase system iso-octane buffer pH 3.95 after 800 transfers. The light-yellow oil with molecular formula C. 4H2o04 and a pKy( value of 2.8 absorbs in the UV region... 

Hydrogenation of hulupone and cohulupone in the presence of platinum(IV) oxide or palladium(il) chloride as catalysts affords in both cases a hexahydroderivative and an octahydroderivative (2,16,22). With palladium on barium sulfate only a hexahydrohulupone or a hexahydrocohulupone is formed (87%). Thus hexahydrocohulupone gives 2-(3-methylbutanoyl)-5,5-bis(3-methylbutyl)-3,4-di-hydroxy-2-cyclopentenone (211, Fig. 88), which also may be considered as 5-(3-methylbutyl)dihydrocohumulinic acid. Cohulupone leads to 5,5-bis(3-methylbutyl)-3,4-dihydroxy-2-(2-methylpropanoyl)-2-cyclopentenone or 5-(3-methylbutyl)dihydro-cohumulinic acid (210, Fig. 87). This compound is identical to that obtained by sequential oxidation, reduction and alkaline treatment of hexahydrocolupulone (see 13.1.1.2.2.). Compound 210 (melting point 48°C) is isolated from the band with distribution coefficient 0.475 after 450 transfers in the two-phase system iso-octane acetate buffer in methanol water 58 42 with pH 5.45 (8). The molecular formula is C19H32O4 and the pK/ value in methanol water 1 1 is 4.1. In the H NMR spectrum... 

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