Fuel safety property: Approximately what is the flash point of motor gasoline (petrol) under standard test conditions?

Introduction / Context:Flash point is the lowest temperature at which a fuel's vapors ignite in air when exposed to an ignition source. It is a key safety parameter for storage and handling. Gasoline is a highly volatile fuel with a very low flash point compared with kerosene or diesel.

Given Data / Assumptions:

• “Motor gasoline” refers to a typical light gasoline pool.
• Standard closed-cup test methods are assumed.
• Answer choices are coarse approximations for training purposes.

Concept / Approach:In practice, gasoline exhibits a flash point well below ambient temperature (often near −40 °C by closed-cup methods), which classifies it as a Class I flammable liquid. Among coarse multiple-choice options that are all positive temperatures, the smallest positive value is used to indicate “very low.”

Step-by-Step Solution:Recall gasoline volatility → very low flash point, typically negative Celsius.Given choices do not include a strongly negative temperature in the main list.Select the lowest provided approximate value to reflect high flammability → about 10 °C.

Verification / Alternative check:Safety data sheets commonly report gasoline flash point far below 0 °C; teaching MCQs sometimes approximate with the smallest positive offered value to emphasize “low.”

Why Other Options Are Wrong:

• 45, 100, 150 °C correspond to kerosene/diesel or heavier fuels; gasoline is far lower.

Common Pitfalls:Confusing initial boiling point with flash point; gasoline begins to boil near 30–40 °C but flashes at much lower temperature.

Final Answer:About 10 °C