What type of bond exists between carbon atoms in alkanes?

• A. Single bonds
• B. Double bonds
• C. Triple bonds
• D. Aromatic bonds

Answer: (A)

Alkanes are saturated hydrocarbons, which means all the carbon–carbon bonds are single covalent bonds. In a typical alkane, each carbon forms four single bonds: three with hydrogen and one with another carbon. That single C–C bond is a sigma bond formed by end-to-end overlap of sp3 hybrid orbitals, and it allows rotation around the bond. If there were double or triple bonds, you’d have alkenes or alkynes with fewer hydrogens, and aromatic bonds occur in rings with delocalized electrons—properties not characteristic of alkanes. So the bonds between carbon atoms in alkanes are single bonds.