Hydrocarbons are organic molecules that solely consist of hydrogen and carbon atoms. These compounds are considered saturated if they contain the maximum number of hydrogen atoms. Degrees of unsaturation are structural features that cause a compound to have less than the maximum number of hydrogen atoms possible, and cause the hydrocarbon to be considered unsaturated. In hydrocarbons, degrees of unsaturation consist of ring structures and pi bonds (double and triple bonds). The following formulas can be used to determine whether a molecular formula represents an alkane, alkene, or alkyne (assuming that the hydrocarbons are not ring structures, and that the unsaturated compounds only have one double or triple bond).
Alkanes: CnH2n+2
Alkenes: CnH2n
Alkynes: CnH2nâ2
