In the bottom-to-top order of fractions, which is directly above bitumen?

• A. Heavy fuel oil
• B. Lubricating oil
• C. Diesel
• D. Kerosine

Answer: (A)

In fractional distillation, components are arranged by boiling point from bottom to top: heavier, higher-boiling fractions stay lower, while lighter, lower-boiling ones rise higher. Bitumen is the heaviest residue that remains at the bottom, so the next fraction above it must have a lower boiling point but still be quite heavy. That is heavy fuel oil, which sits directly above bitumen in the bottom-to-top order. Lighter fractions—lubricating oil, diesel, kerosene, and so on—continue above it as you move up the column.