are all alkanes hydrocarbons
1 Alkanes are Saturated Hydrocarbons. 2  They consist of the elements Carbon and Hydrogen, and all the bonds between the Carbon atoms are single bonds. 3  They have the general formula CnH2n+2.4  Since all Alkanes are similar in structure and properties, they are called a Homologous Series. Alkanes are Saturated Hydrocarbons. 2  They consist of the elements Carbon and Hydrogen, and all the bonds between the Carbon atoms are single bonds. 3  They have the general formula CnH2n+2.