The flash point for fuel oil #6 is 140 degrees.

• A. 120 degrees
• B. 150 degrees
• C. 130 degrees
• D. 140 degrees

Answer: (D)

The flash point is the lowest temperature at which a liquid can produce enough vapor to ignite in air when an ignition source is present. For fuel oil #6, this value is about 140 degrees Fahrenheit, meaning vapors become ignitable at that temperature. So the correct choice is 140 degrees because it represents the minimum temperature needed for ignition to be possible. The other numbers are either below that threshold, where vapors aren’t sufficient to ignite yet, or above it, where ignition could occur but not at the lowest qualifying temperature.