The Alkanes

The alkanes are hydrocarbons that only contain single covalent bonds between their carbon atoms. This means that they are saturated compounds and are quite unreactive. The simplest alkane has only one carbon atom and is called methane. The second alkane in the series has two carbon atoms and is called ethane.



The third alkane in the series has three carbon atoms and is called propane

When you look at the molecular formula for each of the alkanes, you should notice a pattern developing. For each carbon atom that is added to the molecule, two hydrogen atoms are added.

In other words, each molecule differs from the one before it by CH2. This is called a homologous series. The alkanes have the general formula
CnH2n+2

The alkanes are the most important source of fuel in the world and are used extensively in the chemical industry. Some are gases (e.g. methane and ethane), while others are liquid fuels (e.g. octane, an important component of petrol).