Hydrocar bons

Waxes are water repelling solids that are part of the protective coatings of a number of living things including the leaves of plants the fur of animals and the feathers of birds They are usually mixtures of esters m which both the alkyl and acyl group are unbranched and contain a dozen or more carbon atoms Beeswax for example contains the ester triacontyl hexadecanoate as one component of a complex mixture of hydrocar bons alcohols and esters... 

Another name for aromatic hydrocar bons is arenes. Arenes have properties that are much different from alkanes, alkenes, and alkynes. The most important aromatic hydrocarbon... 

This will generally be tr-ue as we proceed to look at other alkanes as the number of carbon atoms increases, so does the boiling point. All the alkanes with four car bons or less are gases at room temperature and atmospheric pressure. With the highest boiling point of the three, propane is the easiest one to liquefy. We are all faniliar- with propane tanks. These are steel containers in which a propane-rich mixture of hydrocar bons called liquefied petroleum gas (LEG) is maintained in a liquid state under high pressure as a convenient clean-burning fuel. 

Table 1.7 shows that hydrocarbons are extremely weak acids. Among the classes of hydrocar bons, acetylene is a stronger acid than methane, ethane, ethylene, or benzene, but even its is 10 ° smaller than that of water. 

Ethane is the simplest hydrocar bon that can have distinct confonnations. Two, the staggered conformation and the eclipsed conformation, deserve special mention and are illustrated with molecular models in Figure 3.1. 

Organic molecules in which one carbon atom is common to two rings are called spirocyclic compounds. The simplest spirocyclic hydrocar bon is spiropentane, a product... 

Fligher alcohols become more hydrocar bon-like and less water-soluble. 1-Octanol, for exfflnple, dissolves to the extent of only 1 rnL in 2000 rnL of water. As the alkyl chain gets longer, the hydrophobic effect (Section 2.17) becomes more important, to the point that it, more than hydrogen bonding, governs the solubility of alcohols. 

Alkynes are hydrocar bons that contain a carbon-car bon triple bond. Simple alkynes having no other functional groups or rings have the general formula C H2 -2. Acetylene is the simplest alkyne. 

Acetylene and terminal alkynes are more acidic than other hydrocar bons. They have pX s of approximately 26, compared with about 45 for alkenes and about 60 for alkanes. Sodium amide is a strong enough base to remove a proton from acetylene or a terminal alkyne, but sodium hydroxide is not. 

The classification of hydrocar bons as aliphatic or ar omatic took place in the 1860s when it was aheady apparent that there was something special about benzene, toluene, and their- derivatives. Their molecular- for-mulas (benzene is CgHg, toluene is CyKj ) indicate that, like alkenes and alkynes, they are unsaturated and should undergo addition reactions. Under conditions in which bromine, for example, reacts rapidly with alkenes and alkynes, however, benzene proved to be inert. Benzene does react with Br-2 in the presence of iron(III) bromide as a catalyst, but even then addition isn t observed. Substitution occurs instead ... 

One of molecular- orbital theories early successes came in 1931 when Erich Hiickel discovered an interesting pattern in the tt orbital energy levels of benzene, cyclobutadiene, and cyclooctatetraene. By limiting his analysis to monocyclic conjugated polyenes and restricting the structures to planar- geometries, Hiickel found that whether a hydrocar bon of this type was aromatic depended on its number of tt electrons. He set forth what we now call Hiickel s rule ... 

What about a substance with the moleculai fonnula C7H14 This compound cannot be an alkane but may be either a cycloalkane or an alkene, because both these classes of hydrocar bons conespond to the general moleculai fonnula C H2 . Any time a ring or a double bond is present in an organic molecule, its molecular formula has two fewer hydrogen atoms than that of an alkane with the same number of carbons. 

The formation of micelles and their properties are responsible for the cleansing action of soaps. Water that contains sodium stearate removes grease by enclosing it in the hydrocar bon-like interior of the micelles. The grease is washed away with the water, not because it dissolves in the water but because it dissolves in the micelles that are dispersed in the water. Sodium stearate is an example of a soap sodium and potassium salts of other C12-C1S unbranched carboxylic acids possess similar- properties. 

To accommodate the new material on acids and bases in Chapter 1, the orbital hybridization model of bonding in organic compounds has been rewritten and placed in Chapter 2. In keeping with its expanded role. Chapter 2 in now titled Hydrocar bon Frfflneworks. Alkanes. ... 

J. J. Szakasits and R. E. Robinson, Hydrocar bon type deter mination of naphthas and cat-alytically refor med products by automated multidimensional gas chromatography . Anal. Chem. 63 114-120(1991). 

M. G. Block, R. B. Callen and J. H. Stockinger, The analysis of hydrocar bon products obtained from methanol conversion to gasoline using open tubular GC columns and selective olefin absorption , ]. Chromatogr. Sci. 15 504-512 (1977). 

R P. DiSanzo, J. L. Lane and R. E. Yoder, Application of state-of-the-art multidimensional high resolution gas cliromatography for individual component analysis of gasoline range hydrocar bons , 7. Chromatogr. Sci. 26 206-209 (1988). 

Acroldn concentration, 186,187 Adenosine triphosphate, effect of ozone on lung concentration of, 354 Aerosol carbon balance, 50 Aerosol formation, 4, 14, 674-76 ability index, 61 diemical medianisms of, 72 hydrox]4 radical-aromatic hydrocar> bon reaction, 76-81 ozone-olefin reaction, 72-76 condensable species vapor pressure and, 86-90,101... 

J.J. Rang, C.A. Miller, H.H. Hoffmann, and C. Thunig Behavior of Hydrocar-bon/Alcohol Drops Injected into Dilute Solutions of an Amine Oxide Surfactant. Ind. Eng. Chem. Res. 35, 3233 (1996). 

An efficient oxidizing reagent for oxyfunctionalization of saturated hydrocar bons, methyl(trifluoromethyl)dioxirane, can be prepared from aqueous potassium peroxomonosulfale and 1,1,1-tnfluoropropanone [752] The reaction of this reagent with adamantane gives the corresponding tris(hydroxy)adamantane in high yield [755] (equation 80)... 

Both the dipolymers and terpolymers have excellent resistance to hydrocar-bons found in petroleum-based fuels and lubricants The69 5%Fterpolymerresists swelling m blended fuels that contain methanol and can be used in contact with certain phosphate ester-based hydraulic fluids Terpolymers are preferred for contact with aromatic solvents, although either type performs well in higher alcohols VDF-based elastomers dissolve in polar aprotic solvents such as ketones, esters, amides, and certain ethers These elastomers are therefore not suitable for contact with fluids that contain substantial amounts of these solvents because of excessive swell and consequent loss of mechanical properties... 

A six-inch carbon steel elbow in a Los Angeles refinery ruptured releasing a hydrocar-bon/hydrogen mixture at 9 43 P.M. on October 8, 1992. The vapor cloud ignited within seconds. The explosion damaged nearby buildings and shattered windows several miles away and was recorded as a sonic boom at the California Institute of Technology about 20 miles away. [21]... 

McNamee, R. (1996). Retrospective assessment of occupational exposure to hydrocar-bons-job-exposure matrices versus expert evaluation of questionnaires, Occup. Hyg., 3, 137-143. 

The metallations under controlled conditions usually proceed with retention of configuration e.g., (Z)-PhCH=CHCN reacts with LiN(Pr-i>2 in mixed EtjO-hydrocar-bon (a poorly coordinating medium) at — 80°C to provide (Z)-PhCH=CLiCN. However, this undergoes isomerization in the presence of THF or crown ethers to (E)-PhCH = CLiCN ... 

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