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Whether you're celebrating a special occasion, toasting a loved one's wedding, or just for the heck of it, you might have noticed that the bubbles in your glass of sparkling wine don't look the same as those in sodas or some beer. There's just something so satisfying about the way those little bubbles rise in neat and tidy columns. As it turns out, there's a hidden story of physics in why those champagne bubbles are different from anything else that fizzes.

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For starters, let's talk about what's going on with those bubbles. In any sparkling beverage, the bubbles inside are caused by gas that has dissolved into the liquid and some kind of force keeping it there. Usually, that force is pressure, which is why you might notice a loud noise and a sudden rush of has when you open the container. Whether it's a can tab, a bottle cap, or a cork, once the seal is broken and the pressure can release, the gas molecules start to nucleate - or clump - together, so they can rise up out of the liquid. And with champagne, those bubbles come from how it gets fermented.

After champagne is fermented the first time, winemakers add sugar and yeast to kick off a second fermentation. This second ferment takes place after the vintners have bottled and sealed the wine, so carbon dioxide from the fermentation process has nowhere to go except into the wine. And then, when you pop the cork, you release the pressure inside the bottle. That release of pressure is what allows the gas to form bubbles, but the real magic happens *after* the bubbles form.

As they rise, the bubbles form a chain and create wakes behind them, which in the case of champagne, trap the following bubbles and keeps them in that orderly line. The reason they don't jump out of the wake is because of ingredients called "surfactants," which are the same kind of chemicals in soap and detergent that help trap and remove dirt.

Surfactants work by decreasing the tension between two liquids, or in this case, between a liquid and a gas. But the blend of surfactants in champagne are not the same ones in your shower gel; they're fatty acids, and they're part of what makes champagne chapagne-y. These surfactants also reduce the tension between the CO2 bubbles and the liquid, which helps create that stable bubble chain. As each bubble moves, it affects the bubble behind it by leaving a vortex, or tiny areas of swirling liquid. When surfactants are present, both vortices swirl in the same direction, which provides lift that guides both bubbles forward. Other fizzy drinks, like soda and certain beers, don't have the same surfactants. So the two vortices end up swirling in opposite directions, pushing the two bubbles away from each other.

So, that's why soda bubbles are more of a chaotic mess than an orderly line, and we know all this thanks to a 2022 research project that sought to answer exactly this question. And I'm sure it wasn't any fun at all for the scientists who were working on it. They started by pumping different sized gas bubbles through a mixture of water and glycerin. When they added the surfactant sodium dodecyl sulfate, they discovered that the bubble chains became more stable. They also found that chains of larger bubbles were more stable, and that a faster flow rate made the chains less stable.

The researchers say their work could have practical applications that go beyond the possibility of just making your soda fancier. In water treatment plans, for example, aeration tanks add air to water to help encourage the growth of microbes. Knowing how bubbles behave and when they're likely to form could help improve water treatment technologies. So let's pop open a bottle of champagne, or maybe some soda, because that's knowledge worthy of celebration. Cheers.

And when you've got something to celebrate, like winning a math contest or attending a special function, you might think of this video as you pop the champagne. And you can get into that mindset by taking the "contest math II" Brilliant course. Brilliant is an online learning platform with thousands of lessons in math, science, and computer science, and their "contest math II" course has an entire lesson about special functions. Okay, so they're mathematical functions and not champagne-filled galas, but it's the kind of good time you can have without leaving your house. In fact, you can start taking Brilliant courses without even moving from the spot you're in right now. You can just type "brilliant.org/scishow" in your search bar or go to the link in the description down below for a free 30-day trial and 20% off an annual premium Brilliant subscription. And thanks to Brilliant for supporting this SciShow video.

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