A mixture of hydrocarbons whose boiling point is below 200°C (390°F), obtained in the fractional distillation of petroleum. Gasoline is a liquid at ambient temperature, but it volatilizes readily in air to form a flammable mixture. The hydrocarbon fuel is used to power the internal combustion engine. Gasoline is composed primarily of the alkanes (paraffins) hexane, heptane, and octane, plus smaller amounts of higher-boiling alkanes.