Which fraction of crude oil is primarily used as petrol (car fuel)?

• A. Refinery gas
• B. Diesel
• C. Petrol/Gasoline
• D. Lubricating oil

Answer: (C)

Crude oil is separated into fractions by fractional distillation, with each fraction containing hydrocarbons of similar boiling points. Petrol (gasoline) is the light, highly volatile fraction that boils roughly between 40°C and 200°C. This combination of volatility, energy content, and how it burns in spark-ignition engines makes petrol the fuel chosen for most cars. The other options don’t fit car fuel roles: refinery gas is too light and is usually used as fuel for heating or as a feedstock; diesel is heavier and suits diesel engines; lubricating oil is too heavy and is used for lubrication rather than combustion as fuel. So petrol/gasoline is the fraction primarily used as car fuel.