Alkanes are
hydrocarbons that contain only single bonds. When carbons double
back on one another to form a ring, they are called cycloalkanes.
Alkanes are generally unreactive, and have the purpose of holding reactive
functional groups, or the nonalkane portion of a molecule.
Since we
generally don't care about the non-reactive portions of molecules, Organic
Chemists often use the symbol R to represent alkyl substituents.
could be drawn 
to indicate that the straight chain portion of the molecule is
unimportant.
Nomenclature of Alkanes:
| Naming of organic structures, unlike biological classification, follows a rigid set of rules. The International Union of Pure and Applied Chemistry, abbreviated IUPAC, came up with a set of rules that follows the same standards worldwide, and is accepted among all chemists. However, common names of compounds, or names that have historical roots, are still used today for many compounds. |
IUPAC Name:
Propanone |
For a base of one to four carbons, historical root names were chosen. For compounds of five carbons and up, the greek name for the number of carbons is used. The ending of -ane is added to indicate that it is an alkane.
| Number of Carbons | Prefix |
| 1 | Methane |
| 2 | Ethane |
| 3 | Propane |
| 4 | Butane |
| 5 | Pentane |
| 6 | Hexane |
| 7 | Heptane |
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