Watch: Add butane to a bottle of Coke, get a totally unsafe high-powered bottle rocket


#1

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#2

These are the same guys who pulled the magnetron out of a microwave and used it to remotely destroy small appliances. I’m glad they’re in Russia, personally.


#3

No. Not the most dangerous thing I ever did with a butane tank.


#4

I guess that puts the flying-garbage-into-a-lake bit into perspective.


#5

What’s the science here?


#6

Three cheers for homemade directed energy weapons :smiley:

I wouldn’t mind them as my neighbors. Not too close but within a minute or two of walking distance.


#7

can’t wait to see how more aerodynamic and stable versions of this fly.


#8

If they added a few Mentos to the mix that rocket would have the Isp of a gas-core fission motor.


#9

Do tell…


#10

Yeah, I’d be interested in the Science too. The butane isn’t combusting so what’s giving it that kick?


#11

not sure at all what’s happening. The butane is cold - mixes with the coke, co2 comes out of suspension?


#12

(I’m gonna throw out numbers and speculation just to make sure someone comes and humiliates me with correct information, 'cause I want to know the science as well.)

This might be very simple – it looks to me like it’s just CO2 being released, forcing the soda from the open end of the bottle. So I don’t think we need complex chemical explanations.

Butane is quite a bit heavier than air, and substantially heavier than CO2 as well. When the bottle is tipped over, any CO2 being released by the soda (carbonation: those bubbles in your soda are CO2) is being displaced by the heavier butane. The butane and CO2 want to swap places – lighter CO2 to the top of the bottle (nearer the sky); heavier butane to the surface of the soda. Perhaps this swapping of places generates more churn at the soda-butane interface, causing a rapid acceleration in the CO2 release?

This analysis is probably worth only a fraction of one cow turd, but perhaps it will lure a real scientist from the shadows to give us some much-needed learnin’. @lava mentioned that the butane is cold and that might also play a role.


#13

These guys are in an active war zone. It is pretty incredible what they are living through on a day-to-day basis.


#14

And they are obsessed with catching lightning bolts with kites and wire.


#15

Got it. Coke, Butane and Mentos. I have to get this information to Richard Branson.


#16

Good idea. And I’ll get it to John McAfee. Y’know, just in case.


#17

It would be interesting to see if the CO2 actually plays any role. You do need to use a soda bottle, as those are built to take pressure.

I suspect what happens is that when he dispenses butane into the bottle, the liquid butane collects as a liquid on top of the remaining soda (probably freezing a small amount of soda into ice/slush), and floats on top (butane, at 0.6g/cc, is lighter than water, or coke), slowly boiling away into vapor.

When he inverts the bottle, the butane rises to the top of the bottle, in the process absorbing heat from the soda, accelerating the transition from liquid to gas.

As the butane and cola trade positions, the liquid coke now blocks the butane gas from exiting the neck, so pressure rises and the soda is propelled out of the bottle. If the rise in pressure is too fast or the neck of the bottle is blocked with ice, the bottle may burst, as seen at a couple of points in the video.

I suspect this experiment would work just as well with a non-carbonated liquid, even plain water.


#18

Господи помилуй!


#19

Pretty sure that not only is no chemical reaction involved, the CO2 might be a red herring as well.

It looks to me like he isn’t just dispensing butane gas into the bottle, but liquid butane. Which of course does not want to stay a liquid any longer than it has to…

The experiment would be a lot more exciting with an ignition source nearby (intentionally or otherwise). Not more survivable, just more exciting.


#20

That’d be exactly my description. And yes, likely would work with pure water too. (Thought… saline is denser a little, would that add a little more of thrust? Or would that be compensated for by the heavier fuel tank?)