Octane constitutional isomers

In the course of doing this problem, you will write and name the 17 alkanes that, in addition to octane, CH3(CH2)6CH3, comprise the 18 constitutional isomers of C8H18. 

Octane and 2,2,4-trimethylpentane are constitutional isomers and have the same octane number. (3.10)... 

An energy diagram comparing the heats of combustion for three constitutional isomers of octane. 

Isomer ratios (Table 10.20) for the isomerization on n-CM by Isodewaxing to -15°C and by the Pt-silica-alumina catalyst to +22°C, then solvent dewaxed to -15°C, show that from the Pt-SAPO-11 catalyst, the 4-methyl isomer amounts to about 50% more than the 2-methyl case and from the Pt-silicon-alumina, the 4-methyl constitutes are three times as much as the 2-methyl. In the case of n-octane, Pt-SAPO-11 gave about equal quantities of the 2- and 3-isomers, and a similar situation occurred with n-hexadecane, where the 2-, 3-, 4-, and 5- isomer yields were just about equal. 

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