Re: Using carbon dioxide for the propulsion of model rockets

Alexander ---

I have checked around, and the only thing I have found which comes at all 
close to what you have in mind is a toy that was available in the United 
States a few years back. It  used compressed air and water to propel a 
small plastic rocket to one or two hundred feet altitude.  After filling 
the body three quarters of the way full with water, a small hand pump 
similar to a bicycle pump was used to force air into the rocket under 
pressure. Releasing the rocket from the pump nozzle allowed the pressure to 
force the water out of the rocket, and it flew away.

I think your idea will only work for very small rockets. Most of the inner 
volume will have to be used to hold the water you want to squirt out the 
back. If you want to use baking soda to produce enough gas, you will need 
to allow the reaction to completely pressurize the water before allowing 
any to escape: the reaction will not produce enough pressure for flight if 
you don't do this.

Good luck with your experiments

Kevin