91Ó°ÊÓ

What is the difference between aliphatic and aromatic hydrocarbons?

What do "saturated" and "unsaturated" mean when applied to hydrocarbons? Give examples of a saturated hydrocarbon and an unsaturated hydrocarbon.

Alkenes exhibit geometric isomerism because rotation about the \(\mathrm{C}=\mathrm{C}\) bond is restricted. Explain.

Draw all possible structural isomers for this alkane: \(\mathrm{C}_{7} \mathrm{H}_{16}\)

How many distinct chloropentanes, \(\mathrm{C}_{5} \mathrm{H}_{11} \mathrm{Cl}\), could be produced in the direct chlorination of \(n\) -pentane, \(\mathrm{CH}_{3}\left(\mathrm{CH}_{2}\right)_{3} \mathrm{CH}_{3}\) ? Draw the structure of each molecule.

Draw all possible isomers for the molecule \(\mathrm{C}_{3} \mathrm{H}_{5} \mathrm{Br}\).

The structural isomers of pentane, \(\mathrm{C}_{5} \mathrm{H}_{12}\), have quite different boiling points (see Example 11.1 ). Explain the observed variation in boiling point, in terms of structure.

Draw the structures of \(c i s-2\) -butene and trans-2butene. Which of the two compounds would give off more heat on hydrogenation to butane? Explain.

Suggest two chemical tests that would help you distinguish between these two compounds: (a) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3}\) (b) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}=\mathrm{CH}_{2}\)

What factor determines whether a carbon atom in a compound is asymmetric?