WAEC Chemistry 2014 Paper

Concept:The kerosene fraction of crude oil contains liquid hydrocarbons used for domestic cooking.Explanation:Crude oil is separated into fractions by fractional distillation.Domestic cooking typically uses kerosene, which is a liquid fuel.Kerosene molecules usually contain about $11$ to $15$ carbon atoms.Among the options, $\mathrm{C}_{13}\mathrm{H}_{28}$ has $13$ carbon atoms, so it belongs to the kerosene fraction.$\mathrm{C}_3\mathrm{H}_8$ is LPG gas, $\mathrm{C}_5\mathrm{H}_{12}$ is petrol fraction, and $\mathrm{C}_{20}\mathrm{H}_{42}$ is in the diesel or wax fraction.Answer:C. $\mathrm{C}_{13}\mathrm{H}_{28}$