Hydrocarbons compounds, representation

Two-Dimensional Representation of Chemical Structures. The lUPAC standardization of organic nomenclature allows automatic translation of a chemical s name into its chemical stmcture, or, conversely, the naming of a compound based on its stmcture. The chemical formula for a compound can be translated into its stmcture once a set of semantic rules for representation are estabUshed (26). The semantic rules and their appHcation have been described (27,28). The inverse problem, generating correct names from chemical stmctures, has been addressed (28) and explored for the specific case of naming condensed benzenoid hydrocarbons (29,30). 

For the structural analysis of cyclic fatty acid derivatives (polymerized drying oils, copolymerization products of fatty oils with various hydrocarbons), in principle the same graphical methods can be developed as have been described for the investigation of hydrocarbon mixtures. However, the construction of useful graphical representations is hampered by the fact that reliable data on physical constants are restricted to the normal saturated fatty acids and their methyl and ethyl esters the synthesis of pure unsaturated fatty acids is already extremely difficult, to say nothing of more complicated cyclic or branched compounds. 

When is an isomer not an isomer When it is exactly the same compound The hydrocarbon CeHi4 has only five isomers. Examine these two representations for one of them, hexane. 

The cyclic saturated hydrocarbons, or cychalkanes, have the general formula C 2n-cycloalkanes (and other ring compounds that we will encounter later) are often shown in simplified skeletal form in which each intersection of two lines represents a C atom we mentally add enough H atoms to give each carbon atom four bonds. The first four unsubstituted cycloalkanes and their simplified representations are... 

Structural representations of humic and fulvic acids are purely hypothetical and should just be considered as an attempt to rationalize chemical behavior. Several structural models have been proposed based on data gathered from degradative and nondegradative models. The different proposed models should be considered as complementary since each emphasizes certain particular properties. Briefly, humic acids are macromolecular and complex, and composed of substituted aromatic and aliphatic hydrocarbon core materials. It is probable that some aliphatic and aromatic ring compounds are heterocyclic with N, O, or S as the heteroatom. Segments or some side-chain components in the structures are substantially hydrophobic. In general, however, the... 

In Chapter 14 we shall study in detail a group of unsaturated cyclic hydrocarbons known as aromatic compounds. The compound known as benzene is the prototypical aromatic compound. Benzene can be written as a six-membered ring with alternating single and double bonds, called a Kekule structure after August Kekule, who first conceived of this representation ... 

Alkane al- kan [alkyl+-ane] (1899) n. The generic term for any saturated, aliphatic hydrocarbon, i.e., a compound consisting of carbon and hydrogen only and containing no double or triple bonds. Linear alkanes are representable as C H2 +2 while cyclic alkanes have the general formula C H2 . Examples are propane, C3H8, and cyclohexane, C6H12. 

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