Here's a Question! - Bubble in a Bowl
Baking soda and vinegar are added to a bowl. Once the reaction settles down, soap bubbles are blown towards the bowl. One of the bubbles enters the bowl. What happens to the bubble?
Announcer: Frostbite Theater presents... Cold Cuts! No baloney!
Joanna and Steve: Just science!
Joanna: Hi! I'm Joanna!
Steve: And I'm Steve!
Joanna: Here's a question for you...
Steve: Baking soda and vinegar are added to a bowl.
Joanna: Once the reaction settles down, soap bubbles are blown towards the bowl.
Steve: Since it is frustratingly difficult to precisely aim a soap bubble, a staggering number of them are blown before one, finally, enters the bowl, perfectly.
Joanna: What happens to the bubble?
Does it float out of the bowl?
Steve: Does it float in the bowl, in mid-air, for a time, before popping?
Joanna: Does it grow and cover the top of the bowl, and then pop?
Steve: Or, does it pop immediately, because of course it does.
Joanna: Pause the video now if you'd like to think it over before we show you what happens.
Mixing vinegar and baking soda creates carbon dioxide. Carbon dioxide is denser than air, so it collects in the bowl.
Steve: The bubbles, being mostly air, aren't as dense as the carbon dioxide, so they'll float in the bowl for a time, assuming you can get them in there before the carbon dioxide is diffused away and you have to start over again. Which, for us, with this set-up, was about two minutes.
Joanna: Thanks for watching. I hope you'll join us again soon for another question!
Steve: It's like trying to hit a small thermal exhaust port...
They're pretty loud when they pop.
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