Alkane
Definition and meaning of Alkane in chemistry.
An alkane is a saturated hydrocarbon in which every carbon–carbon bond is a single bond, so each carbon atom is bonded to as many hydrogen atoms as possible. Alkanes follow the general formula CnH2n+2 and make up a homologous series that begins with methane, ethane, and propane.
In more detail
Alkanes can exist as straight chains, branched chains, or rings (cycloalkanes). As the chains get longer their boiling points rise, which is why the shortest alkanes (methane to butane) are gases at room temperature, while longer ones are liquids or solids. Because they contain only strong, non-polar single bonds and no reactive functional groups, alkanes are fairly unreactive, mainly undergoing combustion and substitution reactions.
Key facts
| General formula | CnH2n+2 |
|---|---|
| Bonding | Single bonds only (saturated) |
| Simplest member | Methane (CH4) |
| Field | Organic chemistry |
Methane (CH4), the simplest alkane and the main component of natural gas, is widely used for heating and cooking.
Frequently asked questions
What is the general formula for an alkane?
Alkanes have the general formula CnH2n+2, where n is the number of carbon atoms. For example, propane has 3 carbons, so its formula is C3H8.
Why are alkanes described as saturated?
They are saturated because every carbon–carbon bond is a single bond, so each carbon is bonded to the maximum possible number of hydrogen atoms.