Wives' Tales Confirmed: Tapping a Soda Can

This is self-explanatory to most people I guess, but some don't know about it or how it works, and knowing this little trick could potentially save you or someone you love the heartbreak of opening a can of soda or beer and having it spew everywhere...potentially spilling Coke on your crotch on a first date or staining someone's $80,000 Persian rug. 

 Since way on back I've always heard that you should tap several times on a soda can before you open it, especially if it gets shaken or dropped. At first it sounded like either magic or bullshit, but when I thought about it it made sense. What mattered was that when I tried it it worked, and I've been doing it forever. 

 That was waaay before the Internet, so I had to think about it for a minute. I knew that if it wasn't magic or bullshit, it had to somehow calm down the pressure, but how? I'm not a scientist and I'm going from memory so don't quote me on this, but basically carbonation, aka fizz, is produced when carbonic acid reacts with oxygen in the air, producing CO2, which forms the familiar bubbles that rise to the top and tickle our noses. If you've ever watched a stream of bubbles forming along the inside of a glass of champagne, you've seen this in action.

 Apparently when the bubbles form, they're in a big-ass hurry to get to the surface, but they're kept under pressure and can't rise until the can is opened. If a can gets shaken the acid reacts with the small amount of air at the top of the can, which creates millions of extra bubbles that form all through the liquid and along the sides of the can, and when it's opened and the pressure is released, they rush to the surface, taking the liquid with them, which creates the potentially-heartbreaking spew. 

 I knew that if you dropped a can and tried to open it right away it'd spew to High Heaven, but if you let it sit for a few minutes it'd settle down and you could open it without spewage. I figured the gas was going back into solution or rising to the top of the can and being pressurized. If tapping sped up the process, it must be jarring the bubbles to get them to rise to the top. 

 Although I knew that had to be it, I never bothered to try to confirm it, but a short video about it popped up in my feed, and I wanted to make sure my theory was correct, and it was. I know it's a very simple thing and not Rocket Science (SCIENCE), but it's kinda interesting, and mainly it works. 

 The excess bubbles are all through the liquid and along the inside of the can. They're held in place by pressure, but tapping the can jostles them loose and lets most of them rise to the surface. There's still some extra "PSSHHH" when you open a shaken can that's been tapped a few times, but most of the bubbles have risen to the surface and don't take half the beverage with them. It really works. 

 For those keeping score, bubbles are trapped on the inside of cans (and glasses), even when opened, by tiny pits on the surface of the aluminum or glass, and by a tiny electromagnetic charge. Okay, there's the science (SCIENCE) lesson for the day. 

 So, if you happen to be on a date or standing on an $80,000 Persian rug and you have a can of soda that's all shook up, don't be a goober and open it without tapping on the can a few times. You don't want to spray your date's white silk nightie or have foam all over your crotch, unless you're into it. Have a nice day, and tap that can.