Gasoline is a mixture of compounds called hydrocarbons (compounds of hydrogen and carbon). It is obtained by purifying crude oil by fractional distillation. Gasoline is most commonly referred to as a mixture of compounds, therefore it is a mixture. Gasoline is composed of hydrocarbons combined with different concentrations of ethanol. Pure substances can be either elements or compounds. Mixtures can be eitherhomogeneous or heterogeneous. Another term for a homogeneous mixture is a solution. ... Gasoline is thus a blend of different compounds, so it is a mixture.