Why do you suppose small-ring cycloalkenes like cyclohexene do not exist as cis–trans isomers, whereas large ring cycloalkenes like cyclodecene do show isomerism?

Which of the following substances exist as can cis–trans isomers? Draw both isomers for those that do.

a. 2,3-Dimethyl-2-pentene (condensed structures only)

b. 2-Methyl-2-hexene (both condensed and line structures)

c. 2-Hexene (line structures only)

Write structural formulas for compounds that meet the following descriptions:

a. An alkene, C₆H₁₂, that cannot have cis–trans isomers and whose longest chain is 5 carbons long

Write structural formulas for compounds that meet the following descriptions:

b. An alkene with a chemical formula of C₁₀H₁₂, that has cis–trans isomers and contains a benzene ring.

Which of the following compounds are capable of cis–trans isomerism?

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Name all unbranched ether and alcohol isomers with formula C₅H₁₂O and write their structural formulas.

Identify the compounds in each of the following pairs as structural isomers or not structural isomers: (11.3)

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Indicate whether each of the following pairs represent structural isomers or the same molecule:

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Identify the following pairs of structures as structural isomers, cis–trans isomers, or the same molecule: (11.5, 11.6)

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