G12: Isomers, Hydrocarbons, and Carbon Rings

Even though you likely see gasoline-powered vehicles everyday, you rarely see what gasoline itself looks like! To the eye, gasoline is a pretty uninteresting yellowish-brown liquid. At the molecular level, gasoline is actually made up of a range of different molecules, most of them hydrocarbons (molecules containing only hydrogen and carbon atoms).

The molecular geometries of hydrocarbons are directly related to the physical and chemical properties of these molecules. Molecules that have the same molecular formula but different molecular geometries are called isomers. There are two major classes of isomers: structural-isomers and stereo-isomers.