AVTUR is heavier than AVGAS because it has:

• A. A higher heat energy volume per unit of volume
• B. A higher density
• C. A lower energy content
• D. A higher octane rating

Answer: (A)

Weight per volume comes from density—the mass of the liquid in a given liter. AVTUR (jet fuel) is denser than AVGAS, so a liter of AVTUR weighs more than a liter of AVGAS. For example, AVTUR/jet fuel runs about 0.80 kg per liter, while AVGAS is around 0.72 kg per liter. That higher density directly makes AVTUR heavier per unit volume.

The option about higher heat energy per unit of volume points to energy density, which affects how far you can fly on a given volume, not how heavy the fuel is. Octane rating is about combustion behavior, not weight. So the correct idea is density, not energy content or octane.