Which term is a measure of the density of petroleum liquids?

Which term is a measure of the density of petroleum liquids?

• A. API gravity
• B. Tank pressure
• C. Temperature
• D. Viscosity

Answer: (A)

API gravity measures how dense a petroleum liquid is relative to water. A higher API gravity means the liquid is lighter than water, while a lower API gravity means it’s heavier. This scale is derived from the liquid’s specific gravity at a reference temperature (60°F) and is widely used to classify crudes and fuels because it directly reflects density in a practical, industry-friendly way. For example, a crude with API around 40 is lighter (less dense) than one near API 10. The other options don’t describe density: tank pressure is about pressure, temperature influences density but isn’t a density measure itself, and viscosity is about flow resistance.

API gravity measures how dense a petroleum liquid is relative to water. A higher API gravity means the liquid is lighter than water, while a lower API gravity means it’s heavier. This scale is derived from the liquid’s specific gravity at a reference temperature (60°F) and is widely used to classify crudes and fuels because it directly reflects density in a practical, industry-friendly way. For example, a crude with API around 40 is lighter (less dense) than one near API 10. The other options don’t describe density: tank pressure is about pressure, temperature influences density but isn’t a density measure itself, and viscosity is about flow resistance.