Liquid hydrocarbons can be converted to a mixture of gaseous hydrocarbons by:-
(c) distillation under reduced pressure
Key Idea Lower hydrocarbons exist in gaseous state while higher ones are in liquid state or solid state. On cracking or pyrolysis, the hydrocarbon with higher molecular mass gives a mixture of hydrocarbons having lower molecular mass. Hence, we can say that by cracking a liquid hydrocarbon can be converted into a mixture of gaseous hydrocarbons.