Final answer:
Propane (C3H8) is an alkane and also a hydrocarbon; it has three carbon atoms in its backbone, all connected by single bonds.
Step-by-step explanation:
Propane (C3H8) is a compound with a molecular structure that has a backbone of three carbon (C) atoms, each surrounded by hydrogen (H) atoms. This structure corresponds to the molecular formula C3H8, which falls under the general alkane formula CnH2n+2. Therefore, propane is classified as an alkane, which is a type of hydrocarbon. Alkanes are saturated hydrocarbons, meaning they contain only single bonds between carbon atoms, and no double or triple bonds like those found in alkenes or alkynes.