You are probably familiar with the common water rocket experiment, that uses built up air pressure in a soda bottle to push water out the bottom and shoot the rocket into the sky. Manually pumping air into a soda bottle takes time and effort, so when I saw a video on YouTube where a guy used liquid nitrogen instead, it blew my mind, and I had to try it. I have a friend who built his own liquid nitrogen generator and was itching to try this experiment ever since he saw the same video I did. He came over with a few liters in a dewar and we filled up plastic soda bottles about half way with warm water, then poured liquid nitrogen in next.
The liquid nitrogen floats on top of the water, but boils ferociously because of the extreme temperature difference. When the bottle is inverted, the rapidly expanding gas instantly charges the bottle with pressure and forces the water out the bottom, blasting the bottle high into the sky. I was absolutely blown away by how quickly the reaction takes place, and by how much power is present. My friend had one bottle blow up in his hand while he was experimenting with different nozzle sizes, so needless to say, this experiment is potentially very dangerous, and is intended for demonstrational purposes only. For those of you wondering, the replacement cost on my kitchen window was $170.00. For science!! Are you still reading? If so, leave a comment using the word "concur" in a sentence and let's see who we can confuse in the comments section today :)