Question

If a match is placed on top of a pool of gasoline, the gasoline catches on fire. However, if you spray the gasoline into a fine mist and add heat, it explodes. Explain this phenomenon.

Answer 1

The pool of gasoline has a small surface area that is limited to the expose surface.

The fine must of gasoline has a very much increased surface area, according to reaction laws the rate of chemical reaction is proportional to the expose surface area

Therefore from this, we can see that the fine mist of gasoline combusts very rapidly to the point that its explodes.

The number one hazard of gasoline is fire or explosion. Liquid gasoline does not burn, but gasoline vapors do. Since the vapors are heavier than air, they move along close to the ground and can collect in low areas. Any ignition source (cigarette, match, hot exhaust pipe or any spark) can ignite gasoline vapors. When gasoline vapors ignite, one gallon of gasoline can explode with the same force as 14 sticks of dynamite.

Answer 2

Step-by-step explanation:

From basic knowledge of chemistry, the rate of chemical reaction is proportional to the exposed surface area.

Combustion of the gasoline is a chemical reaction and obeys this law like all other chemical reaction.

In a pool of gasoline, the exposed surface area is limited to the surface above the pool and hence the chemical reaction (combustion) is moderate.

When the gasoline is sprayed into fine mist (atomized), the exposed surface area is greatly maximized allowed more surface area to be involved in the reaction. This increases the rate of the reaction and hence the reaction becomes so spontaneous that it combusts very rapidly and explodes.

This atomization of gas is used in fuel combustion in the internal combustion engine.