(N/A) Hydrocarbons are organic compounds consisting entirely of carbon and hydrogen. They are classified as follows:
$1$. Saturated Hydrocarbons (Alkanes): These contain only carbon-carbon single bonds. All carbons are $sp^3$ hybridized. Examples include methane,ethane,and cyclohexane.
$2$. Unsaturated Hydrocarbons: These contain one or more carbon-carbon double $(-C=C-)$ or triple $(-C\equiv C-)$ bonds. Carbons involved in double bonds are $sp^2$ hybridized,and those in triple bonds are $sp$ hybridized. Examples include ethene,ethyne,and cyclobutene.
$3$. Aromatic Hydrocarbons: These are cyclic compounds containing $(4n+2)$ $\pi$ electrons in the ring,where all ring carbons are $sp^2$ hybridized. Examples include benzene,toluene,and naphthalene.