Alkane
Definition
Hydrocarbons with only single bonds: the calm, unreactive family including methane, propane, and the fuels in gasoline.
Technical definition
Alkanes are saturated hydrocarbons containing only C-C and C-H single bonds, with the general formula CnH2n+2. They undergo combustion and free-radical substitution but are otherwise relatively unreactive.
Example
Butane (C4H10) fuels lighters and methane (CH4) heats homes: both burn to CO2 and water.
Common confusion
Saturated means holding maximum hydrogen. Alkanes cannot add more hydrogen without breaking the carbon skeleton, which is why they are less reactive than alkenes.