Reaction scheme: ethane-ethene-ethin-benzene

To solve, we will compose the equations:
CH3 – CH3 = H2 + H2C = CH2 – ethane dehydrogenation reaction, ethene was obtained;
C2H4 = H2 + C2H2 – ethin is formed in the process of elimination of hydrogen from ethylene;
3C2H2 = C6H6 – trimerization occurs on hot coal, which acts as a catalyst, benzene is released.
Examples of reactions recorded for solution show the relationship of saturated hydrocarbons (alkanes), unsaturated (alkenes), alkynes and aromatic hydrocarbons. The reaction products find practical application, for example, benzene, serves as an additive to fuel for combustion.