Elephant toothpaste experiment cannon?

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The "elephant toothpaste" experiment involves mixing hydrogen peroxide and potassium iodide to create a foamy reaction. Attempting to use this reaction in a sealed pipe to create a cannon-like effect is impractical due to the conservation of momentum. The lightness of the foam means that to achieve significant lift, an impractically high speed would be required. This principle is similar to rocket propulsion, where the exhaust gases must be expelled at high velocities to generate sufficient thrust. Overall, the experiment cannot be effectively used as a propulsion system.
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"elephant toothpaste experiment" cannon?

I saw a video of an experiment called "elephant toothpaste" on youtube, where a guy put hydrogen peroxide and potassium iodine in a graduated cylinder, and it all foamed up, and went out of the graduated cylinder. If you put the chemicals in a pipe with a cap on one end, and a valve on the other, would it shoot it like a cannon? or perhaps it would be powerful enough to be like a jet pack, and you could fly around your neighborhood?
 
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Unfortunately not.
There is something called conservation of momentum.
That means that the speed*mass that you move up must equal the speed*mass of the thing that goes down.
The foam doesn't weigh very much so to lift you 70kg at 1m/s (walking speed) you would have to spit out 70kg of foam at 1m/s or 7kg of foam at 70m/s. Since foam is very light you would need very high speed.
You can see this with rockets, because the mass of the exhaust gas is so small you have to fire it out at very high speed - while with a firehouse sending out heavy water you feel a force at much lower speeds.
 

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