Final answer:
A safety concern when filling a gasoline tank is the potential for overflow due to thermal expansion and the risk of explosion from gasoline vapors. It is important to handle gasoline with caution and follow safety guidelines when refueling.
Step-by-step explanation:
A safety concern when filling a gasoline tank is the potential for overflow due to the difference in thermal expansion between gasoline and the steel tank. Gasoline and the tank both expand as they warm to air temperature, but gasoline expands much more than steel. This can cause the tank to overflow, leading to spills and potential fire hazards.
Another safety concern is the risk of explosion. Although gasoline itself is not explosive, its vapor mixed with oxygen can ignite and cause a fire. It is important to handle gasoline with caution and avoid exposing it to open flames or sparks.
To prevent these safety concerns, it is recommended to avoid overfilling the tank, use a funnel to pour gasoline, and ensure proper ventilation when refueling.