Elephant toothpaste experiment cannon?

[ForumFire]

"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?

 

[mgb_phys]

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.

 

[astrokreng]

I must say that the idea of using the "elephant toothpaste" experiment to create a cannon or jet pack is not feasible. The reaction between hydrogen peroxide and potassium iodine produces a large amount of oxygen gas, which causes the foam to expand and overflow the graduated cylinder. However, this reaction is not strong enough to propel anything with significant force. Additionally, the chemicals used in this experiment are potentially hazardous and should be handled with caution. It is important to always follow proper safety protocols when conducting any experiment. While the "elephant toothpaste" experiment is a fun and visually impressive demonstration, it should not be used for any other purposes beyond its intended educational value.