What is an Alkane?

Alkanes are hydrocarbons that contain only single bonds. These are saturated hydrocarbons, so all carbons in the molecule are bonded to hydrogen at every available site. The general alkane formula is C_nH_2n+2. This means for every one carbon in the alkane, there are two times that number of hydrogens, plus two more.

All alkanes have an "-ane" ending. The prefixes are determined by how many carbons are in the main chain. Some examples of alkanes are propane (C₃H₈), methane (CH₄) and ethane (C₂H₆). The subsequent prefixes are "but-," "pent-," "hex-," "hept-," "oct-," "non-" and "dec-."

The flammability of alkanes make them excellent clean-burning fuels. Waste products from burning alkanes include water and carbon dioxide. Gaseous alkanes are used directly as fuel, and liquid alkanes can combine to form energy sources such as gasoline or kerosene. There are also solid types of alkanes in products such as petroleum jelly and even asphalt.

If the end hydrogen is removed from an alkane, a functional group called an alkyl group results. These alkyl groups attach to other hydrocarbons to create alkane derivatives. Alkane derivatives have the same formulas as other alkanes, but they are structural isomers.

Structural isomers have the same elements in the same proportions, but they are laid out differently in space. Most alkane derivatives are not combustible like regular alkanes. Instead, they are found in plastics, makeup and some liquid laundry detergents.

The naming alkane derivatives follow the system established by the International Union of Pure and Applied Chemistry (IUPAC). The root word is the alkane's name indicated by the number of carbons in the main chain. The name of the alkyl group is taken from the name of the regular alkane with an identical number of carbons. The "-yl" suffix replaces the typical "-ane" ending.

The alkyl group's position is given by a number indicating to which carbon it is attached. If there is more than one of the same alkyl group attached to the hydrocarbon, the Greek prefixes used in most sciences, such as "di-," "tri-," "tetra-" and so forth, are used to indicate how many. If more than one alkyl group is attached to the same carbon chain, they are listed in alphabetical order.