How to Dramatically Demonstrate a Combustion Reaction (Whoosh Bottle Experiment)





Introduction: How to Dramatically Demonstrate a Combustion Reaction (Whoosh Bottle Experiment)

The demonstration is performed with a dry five-gallon (20-Litre)water jug. A volume of 5.0 mL of methanol is added to the jug. The jug is capped and shaken for 30 seconds. After removing the top, excess ethanol is shaken from the jug, and placed in a stoppered container away from the demonstration table. Since these “Whoosh Bottle” demonstrations have caused a variety of accidents, it is imperative to protect against shattering when the ignition of the vapor in the jug occurs. After removing the top and drying the opening of the jug, place the jug on its side under the protection of a small three-sided safety shield1 that is lying on its side on the bench top. This allows for protection of both the demonstrator and audience when ignition occurs.

The demonstration is used to discuss the combustion process. I normally first ignite a small volume of ethanol on a watch glass (behind a safety shield) to describe the slow burning process of the vapors. This provides a sharp contrast to the ignition of a small volume of methanol vaporized in the jug. A variety of combustion/detonation processes may then be discussed.

1. The standard three-sided safety shield, which is recommended for use in performing any hazardous demonstrations



    • Pocket-Sized Contest

      Pocket-Sized Contest
    • Pro Tips Challenge

      Pro Tips Challenge
    • Science of Cooking

      Science of Cooking

    We have a be nice policy.
    Please be positive and constructive.




    Very cool. I remember doing this with the old Glass Water Bottles back in the mid-1970's when I was in school. We got some really great cobble stone flame effects. Good job!

    HEY!!! somebody needs to make an instructable on how to make a pulsejet!

    That would be nice. Alot of them require machining, though.

    not really just install a 1 way valve on the back and thats pretty much the only challenge

    But it would melt(assuming you mean PVC). And if you mean stainless, the 1-way part would be hard to find. And even then it would probably have plastic in it that would melt. Of course you have valveless and valved designs, and the valveless ones wouldnt need a valve thing. But the sizes are pretty critical, i think. I wish i had a lathe and mill. Grizzly offers very nice mini lathes and mills. You can get a full mini lathe, and buy all the common accessories for it, for <$1000. Same with the mill. Not to mention the great customer service. I emailed them, asking what i'd need to start up a mini-lathe and mill, and they sent me back a "report" practically, naming everything I'd need for both of them, as well as other things too.

    yep that is what i would call this also :) a pulse jet (valveless). kiteman did an instructible on a very simple jam jar jet and then tried to create a metal one resulting in a cannon lol.