Rank the following from highest distillation temperature to lowest: Diesel fuel, Jet fuel, Naptha, Gasoline.

Rank the following from highest distillation temperature to lowest: Diesel fuel, Jet fuel, Naptha, Gasoline.

• A. Jet Fuel, Diesel, Naptha, Gasoline
• B. Naptha, Gasoline, Jet Fuel, Diesel
• C. Diesel, Jet Fuel, Naptha, Gasoline
• D. Gasoline, Naptha, Jet Fuel, Diesel

Answer: (C)

When you compare how fractions boil off in a distillation column, heavier molecules require higher temperatures to vaporize. So the heaviest among these fractions will distill last, at the highest temperature, while the lightest will come off first at the lowest temperature. Diesel is the heaviest of the group, so it needs the highest distillation temperature. Jet fuel is lighter than diesel but heavier than naptha and gasoline, so it comes off after diesel. Naptha is heavier than gasoline but lighter than jet fuel, so it distills after jet fuel but before gasoline. Gasoline is the lightest, so it boils away at the lowest temperature. This gives the order from highest to lowest distillation temperature: diesel, jet fuel, naptha, gasoline.

When you compare how fractions boil off in a distillation column, heavier molecules require higher temperatures to vaporize. So the heaviest among these fractions will distill last, at the highest temperature, while the lightest will come off first at the lowest temperature.

Diesel is the heaviest of the group, so it needs the highest distillation temperature. Jet fuel is lighter than diesel but heavier than naptha and gasoline, so it comes off after diesel. Naptha is heavier than gasoline but lighter than jet fuel, so it distills after jet fuel but before gasoline. Gasoline is the lightest, so it boils away at the lowest temperature.

This gives the order from highest to lowest distillation temperature: diesel, jet fuel, naptha, gasoline.